I'm printing from the gentoo box, which will share the printer with my mepis and debian computers. I am configuring CUPS through the web interface (http://localhost:631/admin
Update: Turns out I didn't have serial cable support built into my kernel (oops.) That's all fixed, but I think the problem lies in not being able to select the correct port. Serial #1 and #2 are available, but I think those should be my two 9-pins. I'm going to try editing the printers.conf file directly to see if that helps.
I haven't made any changes to cupsd.conf, but if you want to look at it I can post it. Here is printers.conf:
# Printer configuration file for CUPS v1.1.21rc1
# Written by cupsd on Mon Mar 28 13:13:20 2005
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