w00t. I finally got my qpage server working again.
Note to anyone who uses isapnp devices under kernel 2.4 – if you have a script that runs setserial, run it with the following parameters:
setserial /dev/ttyXX auto_irq skip_test autoconfig
The port and IRQ can change, even the stuff shown under dmesg isn't necessarily right. setserial usually figures it all out.

You'll know if this is a problem because you'll get errrors like:
ttyXX: LSR safety check engaged!
in your kernel message ring buffer (dmesg for those who don't know what I'm talking about)

Anyway, there's my useful content post for the day. w00t!