apt-get update failing at 99%

[Tom Allison <tom@tacocat.net>]

I am running into this repeatedly on one machine in particular.

I don't have a memory problem (apt::cache or hardware).
I've been able to run apt-get update on other boxes in the same network and it 
works OK.  But this keeps stopping at 99% and appears to hang.

And while apt-get update is hung, I can still access aptitude -- so there's no 
lock file...

help?