please remove obsolete language packages for firefox

Binary package hint: language-pack-en-base

When I switch to Karmic's firefox from another version (using the same profile), or when I display the add-ons window from within karmic's firefox, it has complaints about three obsolete add-ons:
Firefox(en-GB) 3.5.2
Xulrunner (en-GB) 1.9.0.8
Xulrunner (en-GB) 1.9.1.2

I'm in the US and don't need or particularly want the en-GB language packs, but the problem here isn't the GB packs, it's that two of the versions are wrong. The current Firefox version is 3.5.3, so the 3.5.2 plugin shows as incompatible, as does the 1.9.0.8. They also both show as uninstallable -- I can disable them but not remove them.

ProblemType: Bug
Architecture: i386
Date: Tue Oct 20 10:59:25 2009
DistroRelease: Ubuntu 9.10
Package: language-pack-en-base 1:9.10+20091016
PackageArchitecture: all
ProcEnviron:
 LC_COLLATE=C
 PATH=(custom, user)
 LANG=en_US
 SHELL=/bin/tcsh
SourcePackage: language-pack-en-base
Uname: Linux 2.6.31.1 i686