Hello everybody: I'm trying to write rules in which fact int attributes and fact String attributes should be compared in condition elements. When I compare them, let's say from int to String, rule when Fact1($intAttr : attrInt1) Fact2(attrString == $intAttr) .... the rule seems to behave OK, whereas when I compare them from String to int, rule when Fact1($stringAttr : attrString1) Fact2(attrInt == $stringAttr) .... I get a RuntimeDroolsException( "Conversion to long not supported from java.lang.String"). I've taken a look at the code which throws the exception, BaseObjectClassField.getLongValue() and found that it only accepts Number and Date objects to be converted to long. ... if ( value instanceof Number ) { return ((Number) value).longValue(); } else if ( value instanceof Date ) { return ((Date) value).getTime(); } ... Is it possible to add String to long conversion via Long.parseLong(str) or is there any reason not to allow this conversion?. Thank you again for your time. Best regards, Manuel Ortiz.