Emacs EOF on sys.stdin.readline()

[Shimmie]

In Emacs, I'm always getting EOF back from a readline() call. My program's
along the lines of:

        while 1:
            line = sys.stdin.readline()

I run it using C-c C-c, however the readline() always returns EOF on
everycall. Same thing happens if I use cmd.Cmdloop. If I run the py-shell
though and type the code in, it works fine.

What have I got configured weird?

Emacs 21.1 on WinXP.

Shimmie.