Worklist filtering on XML data

Hi,
I'm testing the worklist filtering that uses the WorklistCriteria Class.
I have a processxml called K2Data that could look like the following:
<K2Data>
<Value1>Data I want to filter on</Value1>
<Value2>Data I dont want to filter on</Value2>
</K2Data>

I'm currently using the following bit of code to set the worklist criteria:

oWorklistCriteria.Platform = "ASP";
oWorklistCriteria.AddFilterField(SourceCode.K2ROM.WCLogical.And, SourceCode.K2ROM.WCField.ProcessXml, "K2Data", SourceCode.K2ROM.WCCompare.Like, "*" + Filter + "*");

Where Filter is a value that I pass to my function.

My problem is that it seems as if the filter will basically search all subnodes of the K2Data XML.
Is it possible to somehow set it to only filter using subnode Value1 ?