Outlook won’t work with VPN

Outlook settings: both POP3 and SMTP servers are set to mail..com using SMTP authentication. It works fine on the users laptop while on their local LAN (Win 2003 server w/DNS) and while at home. If they connect to the office 2003 server VPN Outlook fails despite the fact that the laptop can resolve the name mail..com “Use default gateway on remote” is deselected in the VPN properties of the laptop.

Thanks in advance,
Steve