[Zope] Trapping external database errors

Hi, I have a Zope site connected to a SQL-server 7 database. It's nescesary to update, add information through the Zope site. Is there a elegant way to trap errors generated by the external database server. Now, when an user enters a invalid date for example, Zope simply returns a standard error page, with some information generated (i guess) from the ODBC adapter. I know the right thing to do is validating the fields before submitting the form (I have a question on this matter wich I posted earlier). But that said: it must be possible evaluate/trap the outcome of a external database transaction in an elegant way. thanks Henny van der Linde