[Zope] permissions and ODBC

I use zope 2.2.0 and ZODBC-3.1.0b2. I get a strange behavior with ODBC access and permissions. To keep it simple, I have an ODBC-Connection and a SQL-Method. When I execute the SQL-Method everything works fine. When I call the same method from within an DTML-document I get asked for a password and whatever I try (even the super user), nothing works. I configured proxies, no success. What is wrong, maybe zope version and the ZODBC version do not like each other? Anyone an idea? Jens