If DW built the function it would normally update it. Sometimes you have to open the behaviour to add the aditional fields though.
If you have a page with an Insert/Update record behaviour attached all set up and working. Then added a new form field to the page you would have to add the new form element to the Insert/Update behaviour, otherwise dw doesn't know what you want to do with the contents.
Hope that explains it a bit.
Cheech [Peace][Pipe]
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