[Dovecot] strange behavior with virtual accounts and imap

hi, I've recently setup new mailserver with dovecot and postfix. They use mysql and virtual accounts. All works perfectly except.. There is one group account named info, all the mail is forwarded to every other account. Users download their mail via Outlook (2003, 2007) with imap. If someone downloads email send to info and delete it after that. Outlook stoke the message and doesn't delete it immediately, thats normal. But if later someone else downloads his mail and it have received the same letter to info. The message appear as if it's already deleted by that user. But is supposed to be unreaded. I cant find any info why is this happening. Please help