Will distro upgrade program manage packages installed from experimental repository?

[xwang1976 at email.it]

Hi,
I've just upgraded my system from 8.04 to 8.10 and I have had to 
uninstall non official repositories in order to correctly complete the 
process. Now I see that KDE  4 is changing very fast and so I would like 
to test the 4.2 branch adding the experimental ppa repository, but I 
would like to know if the 8.10 to 9.04 upgrade tool will be able to 
execute the upgrade with such repository.
Thank you,
Xwang