InfoPath Dev

Hi, I have been researching the idea of using an InfoPath form to update a SharePoint list. I have come across numerous posts that detail the procedure but none that address the issue of updating a table with lookup fields.

Matt Faus seems to have answered the question in this post (his second response) but it is pretty old. Is this still true?

OK I did find a more recent post that seems to suggest it can be done, but even after reading it I'm still fuzzy on the syntax. I should also clarify that the tables originated in Access 2010 and were published to SharePoint.

Given: Table "Projects" and Table "Project Costs"

Projects                                         Project Costs

ID     ProjectName                          ID    ProjectName      ProjectCost

 1     A1                                            4    A1                      $5.00

 6     E1                                          12    E1                      $5.00

 7     E2                                          13    E2                      $10.00

If my InfoPath 2010 form is updating the ProjectCost field for project E1, how should the syntax read in my CAML query? Here is what I have:

 <?xml version="1.0" encoding="UTF-8"?>
<Batch OnError="Continue">
    <Method ID="1" Cmd="Update">
        <Field Name="ProjectName">1;#A1</Field>
        <Field Name="ProjectCost"></Field>
    </Method>
</Batch>

 Thanks,

 Rob