Dial-up interfering with broadband

I have broadband internet, but a client with dial-up access. When I dial-up the client, the dial-up takes over the broadband and I can't access the internet for research or anything. For instance, when I try to open my mail, my internet is looking for the server with the client's hospital name in it.

Is there any way I can designate the dialup to not be part of the internet?

Thanks in advance.
deb

Follow Ups:

• What exactly you mean by 'client'? - confused. 00:22:47 12/12/04 (4)
  • Client - Deb 03:01:33 12/12/04 (3)
    • confused - me 18:33:02 12/13/04 (2)
      • Dial-up - Deb 18:54:55 12/13/04 (1)
        • think I got it - me 20:37:46 12/13/04 (0)