[Zope-dev] Data.fs

Hi, I'am using Zope 2.1.6 and my Data.fs is going corrupted and i don't have found a way for backup this file. My Questions are: is there a way to delete the last transaction from Data.fs, and can i backup the Data.fs when Zope is running. Is the backup of Data.fs inconsitent when i make the backup at the same time a user writes to it? I want to a backup Data.fs twice a day. so i want to have 14 data.fs files every week. On this way i can find out when the error occurs and i can restore an older version of Data.fs. as