Based on the very helpful posts on this thread, I was able to add the proper repository, then apt-get remove python-hildondesktop, and then the apt-get install python2.5-hildondesktop,
but I got the following error:

Nokia-N810-51-3:~# apt-get install python2.5-hildondesktop
Reading package lists... Done
Building dependency tree... Done
The following NEW packages will be installed:
python2.5-hildondesktop
0 upgraded, 1 newly installed, 0 to remove and 46 not upgraded.
4 not fully installed or removed.
Need to get 48.9kB of archives.
After unpacking 217kB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
python2.5-hildondesktop
Install these packages without verification [y/N]? y
Get:1 http://repository.maemo.org chinook/free python2.5-hildondesktop 0.0.2-1 [48.9kB]
Fetched 48.9kB in 14s (3422B/s)
(Reading database ... 24764 files and directories currently installed.)
Unpacking python2.5-hildondesktop (from .../python2.5-hildondesktop_0.0.2-1_armel.deb) ...
dpkg: error processing /var/cache/apt/archives/python2.5-hildondesktop_0.0.2-1_armel.deb (--unpack):
trying to overwrite `/usr/lib/python2.5/site-packages/hildondesktop.la', which is also in package python-hildondesktop
Errors were encountered while processing:
/var/cache/apt/archives/python2.5-hildondesktop_0.0.2-1_armel.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
Nokia-N810-51-3:~#

What is the resolution for this error?