diff --git a/connectors/odata/translator-odata4/src/main/java/org/teiid/translator/odata4/ODataFilterVisitor.java b/connectors/odata/translator-odata4/src/main/java/org/teiid/translator/odata4/ODataFilterVisitor.java
index 3b741226cd..54d3ac0007 100644
--- a/connectors/odata/translator-odata4/src/main/java/org/teiid/translator/odata4/ODataFilterVisitor.java
+++ b/connectors/odata/translator-odata4/src/main/java/org/teiid/translator/odata4/ODataFilterVisitor.java
@@ -115,6 +115,10 @@ private BaseColumn setCurrentExpression(Expression leftExpression) {
         } else {
             currentExpression = null;
         }
+        //we are really looking for the native type, if it's not set then don't bother
+        if (currentExpression != null && currentExpression.getNativeType() == null) {
+            currentExpression = null;
+        }
         return old;
     }
 
@@ -124,16 +128,10 @@ protected void appendRightComparison(Comparison obj) {
 
     @Override
     public void visit(IsNull obj) {
-        if (obj.isNegated()) {
-            this.filter.append(NOT.toLowerCase()).append(Tokens.LPAREN);
-        }
         appendNested(obj.getExpression());
         this.filter.append(Tokens.SPACE);
-        this.filter.append("eq").append(Tokens.SPACE); //$NON-NLS-1$
+        this.filter.append(obj.isNegated()?"ne":"eq").append(Tokens.SPACE); //$NON-NLS-1$ //$NON-NLS-2$
         this.filter.append(NULL.toLowerCase());
-        if (obj.isNegated()) {
-            this.filter.append(Tokens.RPAREN);
-        }
     }
 
     private void appendNested(Expression ex) {
diff --git a/connectors/odata/translator-odata4/src/test/java/org/teiid/translator/odata4/TestODataSQLVistor.java b/connectors/odata/translator-odata4/src/test/java/org/teiid/translator/odata4/TestODataSQLVistor.java
index 427fe8b0ca..523399676c 100644
--- a/connectors/odata/translator-odata4/src/test/java/org/teiid/translator/odata4/TestODataSQLVistor.java
+++ b/connectors/odata/translator-odata4/src/test/java/org/teiid/translator/odata4/TestODataSQLVistor.java
@@ -225,7 +225,7 @@ public void testOrderByMultiple() throws Exception {
     @Test
     public void testisNotNull() throws Exception {
     	helpExecute("SELECT UserName FROM People WHERE UserName is NOT NULL", 
-    	        "People?$select=UserName&$filter=not(UserName eq null)");
+    	        "People?$select=UserName&$filter=UserName ne null");
     }    
 
     @Test
@@ -253,7 +253,13 @@ public void testSelectFromNavigationTable2() throws Exception {
     public void testSelectFromComplexTable() throws Exception {
         helpExecute("SELECT * FROM People_AddressInfo where Address = 'foo'", 
                 "People?$select=UserName,AddressInfo&$filter=AddressInfo/Address eq 'foo'");
-    }     
+    }
+    
+    @Test
+    public void testConvert() throws Exception {
+        helpExecute("select username from People where convert(gender, integer) = 1", 
+                "People?$select=UserName&$filter=cast(Gender,Edm.Int32) eq 1");
+    }
     
 }
 
diff --git a/olingo/src/test/java/org/teiid/olingo/TestODataIntegration.java b/olingo/src/test/java/org/teiid/olingo/TestODataIntegration.java
index affb51e721..59268a9922 100644
--- a/olingo/src/test/java/org/teiid/olingo/TestODataIntegration.java
+++ b/olingo/src/test/java/org/teiid/olingo/TestODataIntegration.java
@@ -288,6 +288,15 @@ public void testFilterExpression() throws Exception {
         response = http.GET(baseURL + "/loopy/vm1/G1?$filter=true");
         assertEquals(200, response.getStatus());
     }
+    
+    @Test
+    public void testFilterIsNotNull() throws Exception {
+        //should work, but does not due to https://issues.apache.org/jira/browse/OLINGO-1245
+        //ContentResponse response = http.GET(baseURL + "/loopy/vm1/G1?$filter=not(" + Encoder.encode("e1 eq null") +")");
+        
+        ContentResponse response = http.GET(baseURL + "/loopy/vm1/G1?$filter=" + Encoder.encode("e1 ne null"));
+        assertEquals(response.getContentAsString(), 200, response.getStatus());
+    }
 
     @Test
     public void testEntitySet() throws Exception {