A mail contact in Exchange 2007 that points to a Gmail account and the complaint was that they did not get proper calendar invites, they got a text email with the dreaded winmail.dat
The fix is to edit the mail contact in Exchange and change the Rich Text Format to Never for the contact.
I have not been able to create MS Exchange 2007 accounts from perl, the only method i have found that works is to call the PowerShell command to create the account. Below is an example.
system qq[PowerShell.exe -PSConsoleFile "C:\\Program Files\\Microsoft\\Exchange Server\\Bin\\ExShell.psc1" -Command ". {Enable-Mailbox -Identity fitsuny\\] . $adUser->samaccountname . qq[ -Alias ] . $adUser->samaccountname . qq[ -Database $database] . $value. qq[}"];