diff --git a/src/ol/parser/ogc/filter_v1.js b/src/ol/parser/ogc/filter_v1.js
index b390e61db6..1deca301fa 100644
--- a/src/ol/parser/ogc/filter_v1.js
+++ b/src/ol/parser/ogc/filter_v1.js
@@ -12,6 +12,8 @@ goog.require('ol.expr.Identifier');
 goog.require('ol.expr.Literal');
 goog.require('ol.expr.Logical');
 goog.require('ol.expr.LogicalOp');
+goog.require('ol.expr.Math');
+goog.require('ol.expr.MathOp');
 goog.require('ol.expr.Not');
 goog.require('ol.expr.functions');
 goog.require('ol.parser.XML');
@@ -28,34 +30,49 @@ ol.parser.ogc.Filter_v1 = function() {
   this.readers = {
     'http://www.opengis.net/ogc': {
       _expression: function(node) {
-        var obj, source = '';
+        var expressions = [];
+        var obj, value, numValue, expr;
         for (var child = node.firstChild; child; child = child.nextSibling) {
           switch (child.nodeType) {
             case 1:
               obj = this.readNode(child);
               if (obj.property) {
-                var name = obj.property.getName();
-                source += (source !== '') ? '+' + name : name;
+                expressions.push(obj.property);
               } else if (goog.isDef(obj.value)) {
                 return obj.value;
               }
               break;
             case 3: // text node
             case 4: // cdata section
-              if (source !== '') {
-                source += '+';
-              }
-              if (isNaN(goog.string.toNumber(child.nodeValue))) {
-                source += goog.string.quote(goog.string.trim(child.nodeValue));
-              } else {
-                source += goog.string.trim(child.nodeValue);
+              value = goog.string.trim(child.nodeValue);
+              // no need to concatenate empty strings
+              if (value) {
+                // check for numeric values
+                numValue = goog.string.toNumber(value);
+                if (!isNaN(numValue)) {
+                  value = numValue;
+                }
+                expressions.push(new ol.expr.Literal(value));
               }
               break;
             default:
               break;
           }
         }
-        return ol.expr.parse(source);
+        // if we have more than one property or literal, we concatenate them
+        var num = expressions.length;
+        if (num === 1) {
+          expr = expressions[0];
+        } else {
+          expr = new ol.expr.Literal('');
+          if (num > 1) {
+            var add = ol.expr.MathOp.ADD;
+            for (var i = 0; i < num; ++i) {
+              expr = new ol.expr.Math(add, expr, expressions[i]);
+            }
+          }
+        }
+        return expr;
       },
       'Filter': function(node, obj) {
         var container = {
@@ -217,7 +234,8 @@ ol.parser.ogc.Filter_v1 = function() {
             ol.expr.functions.DWITHIN);
       },
       'Distance': function(node, obj) {
-        obj.distance = new ol.expr.Literal(this.getChildValue(node));
+        var value = goog.string.toNumber(this.getChildValue(node));
+        obj.distance = new ol.expr.Literal(value);
         obj.distanceUnits = new ol.expr.Literal(node.getAttribute('units'));
       }
     }
@@ -328,12 +346,8 @@ ol.parser.ogc.Filter_v1 = function() {
       },
       'Literal': function(expr) {
         goog.asserts.assert(expr instanceof ol.expr.Literal);
-        var value = expr.getValue();
-        if (value instanceof Date) {
-          value = value.toISOString();
-        }
         var node = this.createElementNS('ogc:Literal');
-        node.appendChild(this.createTextNode(value));
+        node.appendChild(this.createTextNode(expr.getValue()));
         return node;
       },
       'LowerBoundary': function(expr) {
diff --git a/test/spec/ol/parser/ogc/filter_v1_0_0.test.js b/test/spec/ol/parser/ogc/filter_v1_0_0.test.js
index 87ec4afffa..be7de99cee 100644
--- a/test/spec/ol/parser/ogc/filter_v1_0_0.test.js
+++ b/test/spec/ol/parser/ogc/filter_v1_0_0.test.js
@@ -4,9 +4,9 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
 
   var parser = new ol.parser.ogc.Filter_v1_0_0();
 
-  describe('#readwrite', function() {
+  describe('reading and writing', function() {
 
-    it('intersects filter read / written correctly', function(done) {
+    it('handles intersects', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/intersects.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -23,7 +23,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('within filter read / written correctly', function(done) {
+    it('handles within', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/within.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -39,7 +39,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('contains filter read / written correctly', function(done) {
+    it('handles contains', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/contains.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -56,18 +56,18 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('between filter read / written correctly', function(done) {
+    it('handles between', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/between.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
-        expect(filter instanceof ol.expr.Logical).to.be.ok();
+        expect(filter).to.be.a(ol.expr.Logical);
         expect(filter.getOperator()).to.equal(ol.expr.LogicalOp.AND);
-        expect(filter.getLeft() instanceof ol.expr.Comparison).to.be.ok();
+        expect(filter.getLeft()).to.be.a(ol.expr.Comparison);
         expect(filter.getLeft().getOperator()).to.equal(
             ol.expr.ComparisonOp.GTE);
         expect(filter.getLeft().getLeft().getName()).to.equal('number');
         expect(filter.getLeft().getRight().getValue()).to.equal(0);
-        expect(filter.getRight() instanceof ol.expr.Comparison).to.be.ok();
+        expect(filter.getRight()).to.be.a(ol.expr.Comparison);
         expect(filter.getRight().getOperator()).to.equal(
             ol.expr.ComparisonOp.LTE);
         expect(filter.getRight().getLeft().getName()).to.equal('number');
@@ -78,18 +78,18 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('between filter read correctly without literals', function(done) {
+    it('handles between without literals', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/between2.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
-        expect(filter instanceof ol.expr.Logical).to.be.ok();
+        expect(filter).to.be.a(ol.expr.Logical);
         expect(filter.getOperator()).to.equal(ol.expr.LogicalOp.AND);
-        expect(filter.getLeft() instanceof ol.expr.Comparison).to.be.ok();
+        expect(filter.getLeft()).to.be.a(ol.expr.Comparison);
         expect(filter.getLeft().getOperator()).to.equal(
             ol.expr.ComparisonOp.GTE);
         expect(filter.getLeft().getLeft().getName()).to.equal('number');
         expect(filter.getLeft().getRight().getValue()).to.equal(0);
-        expect(filter.getRight() instanceof ol.expr.Comparison).to.be.ok();
+        expect(filter.getRight()).to.be.a(ol.expr.Comparison);
         expect(filter.getRight().getOperator()).to.equal(
             ol.expr.ComparisonOp.LTE);
         expect(filter.getRight().getLeft().getName()).to.equal('number');
@@ -98,11 +98,11 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('null filter read / written correctly', function(done) {
+    it('handles null', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/null.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
-        expect(filter instanceof ol.expr.Comparison).to.be.ok();
+        expect(filter).to.be.a(ol.expr.Comparison);
         expect(filter.getLeft().getName()).to.equal('prop');
         expect(filter.getRight().getValue()).to.equal(null);
         var output = parser.write(filter);
@@ -111,7 +111,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('BBOX written correctly', function(done) {
+    it('writes BBOX', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/bbox.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(
@@ -126,7 +126,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('BBOX without geometry name written correctly', function(done) {
+    it('writes BBOX without geometry name', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/bbox_nogeom.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(
@@ -140,7 +140,28 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('DWithin written correctly', function(done) {
+    it('reads DWithin', function(done) {
+      var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/dwithin.xml';
+      afterLoadXml(url, function(xml) {
+        var filter = parser.read(xml);
+        expect(filter).to.be.a(ol.expr.Call);
+        var callee = filter.getCallee();
+        expect(callee).to.be.a(ol.expr.Identifier);
+        var name = callee.getName();
+        expect(name).to.equal(ol.expr.functions.DWITHIN);
+        var args = filter.getArgs();
+        expect(args.length).to.equal(5);
+        var distance = args[1];
+        expect(distance).to.be.a(ol.expr.Literal);
+        expect(distance.getValue()).to.equal(1000);
+        var units = args[2];
+        expect(units).to.be.a(ol.expr.Literal);
+        expect(units.getValue()).to.equal('m');
+        done();
+      });
+    });
+
+    it('writes DWithin', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/dwithin.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(new ol.expr.Identifier(
@@ -161,9 +182,9 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
 
   // the Filter Encoding spec doesn't allow for FID filters inside logical
   // filters however, to be liberal, we will write them without complaining
-  describe('#logicalfid', function() {
+  describe('logical fid', function() {
 
-    it('logical filter [OR] with fid filter written correctly', function(done) {
+    it('writes logical [OR] with fid', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/logicalfeatureid.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Logical(ol.expr.LogicalOp.OR,
@@ -179,7 +200,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
       });
     });
 
-    it('logical filter [AND] with fid filter written correctly',
+    it('writes logical [AND] with fid',
         function(done) {
           var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/' +
               'logicalfeatureidand.xml';
@@ -197,7 +218,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
           });
         });
 
-    it('logical filter [NOT] with fid filter written correctly',
+    it('writes logical [NOT] with fid',
         function(done) {
           var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/' +
               'logicalfeatureidnot.xml';
@@ -213,30 +234,8 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
 
   });
 
-  describe('#date', function() {
-
-    it('date writing works as expected', function(done) {
-      var url = 'spec/ol/parser/ogc/xml/filter_v1_0_0/betweendates.xml';
-      afterLoadXml(url, function(xml) {
-        // ISO 8601: 2010-11-27T18:19:15.123Z
-        var start = new Date(Date.UTC(2010, 10, 27, 18, 19, 15, 123));
-        // ISO 8601: 2011-12-27T18:19:15.123Z
-        var end = new Date(Date.UTC(2011, 11, 27, 18, 19, 15, 123));
-        var filter = new ol.expr.Logical(ol.expr.LogicalOp.AND,
-            new ol.expr.Comparison(ol.expr.ComparisonOp.GTE,
-            new ol.expr.Identifier('when'), new ol.expr.Literal(start)),
-            new ol.expr.Comparison(ol.expr.ComparisonOp.LTE,
-            new ol.expr.Identifier('when'), new ol.expr.Literal(end)));
-        var output = parser.write(filter);
-        expect(goog.dom.xml.loadXml(output)).to.xmleql(xml);
-        done();
-      });
-    });
-
-  });
-
-  describe('_expression reader works as expected', function() {
-    it('_expression reader handles combined propertyname and literal',
+  describe('_expression reader', function() {
+    it('handles combined propertyname and literal',
         function() {
           var xml = '<ogc:UpperBoundary xmlns:ogc="' +
               'http://www.opengis.net/ogc">10</ogc:UpperBoundary>';
@@ -244,7 +243,7 @@ describe('ol.parser.ogc.Filter_v1_0_0', function() {
               '_expression'];
           var expr = reader.call(parser, goog.dom.xml.loadXml(
               xml).documentElement);
-          expect(expr instanceof ol.expr.Literal).to.be.ok();
+          expect(expr).to.be.a(ol.expr.Literal);
           expect(expr.getValue()).to.equal(10);
           xml = '<ogc:UpperBoundary xmlns:ogc="http://www.opengis.net/ogc">' +
               'foo<ogc:PropertyName>x</ogc:PropertyName>bar</ogc:UpperBoundary>';
diff --git a/test/spec/ol/parser/ogc/filter_v1_1_0.test.js b/test/spec/ol/parser/ogc/filter_v1_1_0.test.js
index 9d7d06bd3d..b39fc59a0f 100644
--- a/test/spec/ol/parser/ogc/filter_v1_1_0.test.js
+++ b/test/spec/ol/parser/ogc/filter_v1_1_0.test.js
@@ -4,9 +4,9 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
 
   var parser = new ol.parser.ogc.Filter_v1_1_0();
 
-  describe('#readwrite', function() {
+  describe('reading and writing', function() {
 
-    it('filter read correctly', function(done) {
+    it('reads filter', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/test.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -45,7 +45,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('matchCase read correctly', function() {
+    it('reads matchCase', function() {
       var cases = [{
         str:
             '<ogc:Filter xmlns:ogc="http://www.opengis.net/ogc">' +
@@ -119,7 +119,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       }
     });
 
-    it('BBOX filter written correctly', function(done) {
+    it('writes BBOX', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/bbox.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -129,7 +129,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('BBOX filter without property name written correctly', function(done) {
+    it('writes BBOX without property name', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/bbox_nogeomname.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -139,7 +139,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('Intersects filter read / written correctly', function(done) {
+    it('handles intersects', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/intersects.xml';
       afterLoadXml(url, function(xml) {
         var filter = parser.read(xml);
@@ -149,7 +149,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('Filter functions written correctly', function(done) {
+    it('handles functions', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/function.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(new ol.expr.Identifier(
@@ -165,7 +165,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('Custom filter functions written correctly', function(done) {
+    it('writes custom functions', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/customfunction.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Logical(ol.expr.LogicalOp.AND,
@@ -179,7 +179,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('Nested filter functions written correctly', function(done) {
+    it('writes nested functions', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/nestedfunction.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(new ol.expr.Identifier(
@@ -197,7 +197,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('matchCase written correctly on Like filter', function(done) {
+    it('writes matchCase on like', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/likematchcase.xml';
       afterLoadXml(url, function(xml) {
         var filter = new ol.expr.Call(
@@ -211,7 +211,7 @@ describe('ol.parser.ogc.Filter_v1_1_0', function() {
       });
     });
 
-    it('sortBy written correctly on Like filter', function(done) {
+    it('writes sortBy on like', function(done) {
       var url = 'spec/ol/parser/ogc/xml/filter_v1_1_0/sortby.xml';
       afterLoadXml(url, function(xml) {
         var writer = parser.writers['http://www.opengis.net/ogc']['SortBy'];
diff --git a/test/spec/ol/parser/ogc/xml/filter_v1_0_0/betweendates.xml b/test/spec/ol/parser/ogc/xml/filter_v1_0_0/betweendates.xml
deleted file mode 100644
index 3ad5b0131e..0000000000
--- a/test/spec/ol/parser/ogc/xml/filter_v1_0_0/betweendates.xml
+++ /dev/null
@@ -1,11 +0,0 @@
-<ogc:Filter xmlns:ogc="http://www.opengis.net/ogc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/ogc http://schemas.opengis.net/filter/1.0.0/filter.xsd">
-    <ogc:PropertyIsBetween>
-        <ogc:PropertyName>when</ogc:PropertyName>
-        <ogc:LowerBoundary>
-            <ogc:Literal>2010-11-27T18:19:15.123Z</ogc:Literal>
-        </ogc:LowerBoundary>
-        <ogc:UpperBoundary>
-            <ogc:Literal>2011-12-27T18:19:15.123Z</ogc:Literal>
-        </ogc:UpperBoundary>
-    </ogc:PropertyIsBetween>
-</ogc:Filter>
diff --git a/test/spec/ol/parser/ogc/xml/filter_v1_0_0/custombetweendates.xml b/test/spec/ol/parser/ogc/xml/filter_v1_0_0/custombetweendates.xml
deleted file mode 100644
index f12024a9dd..0000000000
--- a/test/spec/ol/parser/ogc/xml/filter_v1_0_0/custombetweendates.xml
+++ /dev/null
@@ -1,11 +0,0 @@
-<ogc:Filter xmlns:ogc="http://www.opengis.net/ogc">
-    <ogc:PropertyIsBetween>
-        <ogc:PropertyName>when</ogc:PropertyName>
-        <ogc:LowerBoundary>
-            <ogc:Literal>2010-11-27</ogc:Literal>
-        </ogc:LowerBoundary>
-        <ogc:UpperBoundary>
-            <ogc:Literal>2011-12-27</ogc:Literal>
-        </ogc:UpperBoundary>
-    </ogc:PropertyIsBetween>
-</ogc:Filter>