I've also had some odd crashes lately, and it doesn't seem to want to remember passwords on the keychain.
What I suspect is that OS-X has got a little corrupt somewhere, maybe the keychain or maybe something else. I could just erase the hard disk and reinstall Tiger, the last OS this will run, but I'd lose some applications etc. Is there some sort of utility I can run to check things?
Later - eventually got it working after three router reboots, no idea what the problem was.