InfoPath Dev

UGH! I am new to InfoPath, but I didn't think I was this stupid. Hours on this problem, and I have tried many things. I have a drop down menu that selects an item (department code) from a 3 column SP list (department code, department description, & function - departments roll up into functions...

I get this error when trying to publish a browser-enabled form. The full error is "The filter expression is on external data and could not be validated. It may not be supported in Web browser forms." This is happening because I have cascading drop-down lists that are populated from a Sharepoint...