I'm working on aptitude's dependency resolver at the moment. Mostly
I'm working on some changes to support better UI, but while I have all
the code in my head I'd like to try to fix some of the nagging speed
problems it has. I've already
managed to clear up some simple but large problems with aptitude
safe-upgrade, because I could get them to happen on my computer. The
problem is, most of these problems don't happen on my computer. I
have a half dozen or so specific ideas that might speed aptitude up,
but I don't want to just randomly apply tweaks without some baseline
tests that I can use to make sure that I'm actually making things
better and not just perturbing the code for no reason. 
Plus,
seeing why aptitude is actually running slowly might help when it
comes to finding ways to improve its performance.
So, this is where you come in. If you are using lenny and
aptitude takes a long time to resolve dependencies on your computer
outside of aptitude safe-upgrade, I would like to hear from you.
All you need to do is to run this command when aptitude is slow,
before you upgrade any packages:
$ aptitude-create-state-bundle aptitude-state.tar.bz2
Then, find a way to get the resulting large file to me. Email will
work if your outgoing server accepts it; send to
dburrows@algebraicthunk.net. That will tar up /etc/apt,
/var/lib/apt, /var/cache/apt, and a few other directories: run
aptitude-create-state-bundle --print-inputs to see exactly what it
will include.
Thanks!
[UPDATE]: PS: please also include a brief description of the
problem that you're seeing so I know what to test. Something like,
e.g., when I run
.aptitude full-upgrade it takes thirty minutes to
complete
[UPDATE]: PPS: of course you have to run
aptitude-create-state-bundle before you actually upgrade any
packages! i.e., you must type n at aptitude's command-line prompt
or quit the program if you're using the curses interface.
Otherwise, your state snapshot will just tell me what you upgraded
to, which is only half the information I need (I also need the state
of all packages prior to the upgrade).