A couple of things to look at...

First, make sure you have the parallel port modules. (ppdev, lp,
parport, parport_pc) I don't remember if all of htem are needed, or
if you can get by with just the parport and lp modules.

The second thing is that the default permissions for the parallel
port does not allow access by a normal user.

crw-rw---- 1 root lp 6, 0 Sep 19 23:35 /dev/lp0