Share ADSL for dialin

[Sanjeev]

Hi,

The setup I have so far is like this:
Computer running Windows XP which as an ADSL connected to
it (USB Modem) and also has a network card and a small lan
(3 users) who can share that ADSL connection.

I want to be able to Dial into the the machine and be able
to access the net using the ADSL connection.

The sharing works for the LAN but not for the dialup.

Can anyone help me work this out?

Thanks in advance

Sanjeev