WebDB, form for procedure execution

I can create a form, quite easily to execute a procedure.... however if I leave a field blank (because the procedure CAN accept NULL for that value) webDB does NOT include that parameter in the procedure call.

This requires me to put 'N/A' in the fields I don't need, then FURTHER code to turn 'N/A' into NULL in the procedure.

I can live with this... but IS there a way to have webDB pass ALL parameters to the procedure, even if the field is left blank?

thanks.