fixes #610

Author: wumpz

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -970,7 +970,7 @@ String RelObjectNameWithoutValue() :
       | tk=<K_TABLE> | tk=<K_DATETIMELITERAL> | tk=<K_COMMIT> | tk=<K_PRECISION>
       | tk=<K_INSERT> | tk=<K_INDEX> | tk=<K_PRIMARY> | tk=<K_ENABLE>
 	  | tk=<K_UNSIGNED>
-      | tk=<K_TEMP> | tk=<K_TEMPORARY>
+      | tk=<K_TEMP> | tk=<K_TEMPORARY> | tk=<K_ISNULL> 
       )
 
     { return tk.image; }

src/test/java/net/sf/jsqlparser/test/select/SelectTest.java

@@ -2809,4 +2809,8 @@ public void testProblemSqlFuncParamIssue605() throws JSQLParserException {
     public void testProblemSqlFuncParamIssue605_2() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed("SELECT func(SELECT col1 FROM mytable)");
     }
+    
+    public void testSqlContainIsNullFunctionShouldBeParsed() throws JSQLParserException {
+        assertSqlCanBeParsedAndDeparsed("SELECT name, age, ISNULL(home, 'earn more money') FROM person");
+    }
 }