[Zope] problem with Zope ODBC Database Adapter

Hi, I'm not able to connect to a certain database with the Zope ODBC database adapter. I can connect to other servers with no problems but when I try to connect to this other server I get the error "Invalid connection string". I'm using a connection string like: "DSN username password". I know the name and password are correct because I can connect to it with other client utilities. Has anyone had a problem like this? or see any obvious mistakes I'm making? thanks -Kevin