unhandable error occured (key error: 'libdua5.1-wsapi-fcgi-dev'?)

[uniqueone-85]

hi i'm am still pretty new to ubuntu and i am currently having trouble installing software from the software center and using update manager. when ever i try to install a new program i get the following error message:

There seems to be a programming error in aptdaemon, the software that allows you to install/remove software and to perform other package management related tasks. Please report this error at http://launchpad.net/aptdaemon/+filebug and retry.

the details are this:
Traceback (most recent call last):
File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 179, in _process_transaction
self.commit_packages(*self.trans.packages)
File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 227, in commit_packages
self._commit_changes()
File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 726, in _commit_changes
self._check_obsoleted_dependencies()
File "/usr/lib/python2.6/dist-packages/aptdaemon/worker.py", line 518, in _check_obsoleted_dependencies
for pkg in self._cache:
File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 173, in __iter__
yield self[pkgname]
File "/usr/lib/python2.6/dist-packages/apt/cache.py", line 158, in __getitem__
pkg = self._weakref[key] = Package(self, self._cache[key])
KeyError: 'libdua5.1-wsapi-fcgi-dev'

when ever i run update manager thru terminal i am presented with this same message as above.

I'm am currently using ubuntu 11.04, but i originally installed 10.10. i now realize that the version i am currently using is for developers and there may be no immediate fix, but i have no idea how i upgraded or stop it from automatically upgrading to alpha builds.

Any help will be greatly appreciated.

[uniqueone-85]

it seems the problem may have fixed itself. i also was able to run some updates and upgrades thru terminal so that may have solved it......