How to downgrade beyond Synaptic choices (was Re: How do I "downgrade" evolution and evo-xchange to 2.21?)

[Christopher Biessener]

Brian McKee wrote:
> but you can
> downgrade packages using Synaptic.
>
> <lifted verbatim from http://ubuntuforums.org/showthread.php?t=431146>
>
> Open the manager and search for the package in question. Once found,
> highlight the package and go to the menu item "Packages." Then click
> on "Force Version." Synaptic manager will then alert you to the
> packages that will be added or removed.
>
> Brian
>   
I have seen this option in Synaptic but have not found it useful as it 
only lists a couple very recent choices.  Is there an easy way to 
downgrade beyond the list Synaptic gives you?  I am asking in general 
for downgrading any program.

my system:  (Ubuntu 8-04)
$  uname -rvmo
2.6.24-22-generic #1 SMP Mon Nov 24 18:32:42 UTC 2008 i686 GNU/Linux

Thanks,

Christopher Biessener