[Zope] Conflict error

Hi I have a PAS plugin that pulls user properties from a sql database. Intermittently, I get conflicterrors from the plugin when zope commits its transaction - even though no db changes have been made. Frustratingly, there is very little information in the traceback of actual use, other than the name of the class itself. Is there an easy way to identify what's keeping the database in the transaction so I can correct it? Thanks Miles