I have never experienced such an issue but it looks some files in the OS might have gone corrupt for some reason and that is why you are experiencing such weird issues. I would suggest migrating to the latest and till today the best OS 4.5.0.81. I have seen people complaining about bugs in .55 which have been fixed in the next versions.
Go to this thread to upgrade to the latest OS...
http://www.blackberryforums.com/gene...languages.html