[Zope-dev] Transaction question

I just want to check if things work the way I think (hope) it does. In a transaction, are objects attributes safe from other threads. self._v_mytemp in my request does not conflict with other requests? (I suppose the have to be otherwise REQUEST's would interfere with each other.) I know that _v_* attributes aren't persistent but do they remain active in memory and there by accessible to other requests after the transaction commit? (I suppose class attributes needs to be protected to be thread-safe? Does anybody have an example how to do that?) Regards, Johan