Dialup VPN Connection dropping and not redialing

We are using Windows XP boxes at a remote office to dial in via broadband connection to the home office for a VPN connection. We are doing so by using the ‘log on using dialup connection’ on the login screen. We are connecting to a Windows Server 2003 RAS box. The VPN and the connection are working fine, the problem is, if the broadband connection hiccups while the user is connected then it will not auto redial the connection even with that set in the dialup properties. However, if the user manually dials the connection from the desktop one time, the redial works from then on. Does anyone know how to remedy this?