OK, here's a bit of a strange one.....
I recently set up a network for a friend who just got Broadband in their area.
Time Warner cable box, Linksys wired four port router, iMac G4 1GHz, PowerMac G4 Dual 1GHz MDD (both running Leopard), AirPort Extreme (802.11g, dual-ethernet, no modem).
I did a hard reset on the AirPort, configured it, and updated the firmware to v5.7. When the base station is restarted, it appears for about five min or so via Bonjour. The base station appears in the admin util, and the attached DeskJet 5550 appears available via Bonjour. But then it just goes away. Poof! Nothing in the admin util, and no printer available either.
I was able to connect my PowerBook (also on Leopard) via WiFi, and the base station is pingable, and manageable when connecting using the 'Other' option in the admin util. If I reset the base station, it comes back, but only for about five min again.
Other Bonjour services (iTunes, iChat, file sharing, etc.) work fine between the other computers.
Any thoughts?