If someone can help, i'll be very thankful

I'm currently using the ZCS Open Source 6.0.9, my company is planning on buying the Network Edition but we're waiting for burocratic procedures to end. Mean while I had a problem with a user, who accidently deleted a chunk of mails, and I can't find a way to restore a single account from a previous backup.

I've search the web and the forums but I've only found solutions that only applys for the Network Edition, so I need to find a way to make a restore for my type of ZCS.

Can anyone point me in the right direction. Thanks