[Zope-dev] dtml-try with z-sql

Hi all, I have DTML-Method like below <dtml-try> <dtml-call "deleteUser(USERNAME=USERNAME)"> <dtml-except> An error occurred. Entry was <b>NOT</b> deleted. </dtml-try> deleteUser is Z-SQL method.USERNAME is the argument in Z-SQL method also column name. When i click erase button it succesfully deletes record.But if i enter an invalid username it did not throw any exceptions. Please help REgards