After upgrade to Zimbra 6.0.5 we've got a problem with forwarding messages matching the filter's conditions of mailbox.
I have address firstname.lastname@example.org with alias email@example.com.
The filter is configured to forward messages with To = firstname.lastname@example.org to another address email@example.com.
Everything works perfectly except firstname.lastname@example.org gets mail with header "From:" set to email@example.com. And address of original sender gets lost forever.