Not sure if you have loaded and third party apps but see my fix below and let us know if it helps.
I thought I would share my experience for those having this error and trying to save some time...possibly....rather than doing the initial help desk idea of wipe and reload. I am not guaranteeing you will not have to wipe and reload but this may shed a glimmer of hope for some of the sad folks here. Here it goes and I will plug the post that got me to this point.
What you will need:
A computer (I have only tested with Windows XP so Unix and Mac users may need other methods)
Javaloader (Get it Here http://blackberryforums.pinstack.com...7&d=1149738115
BB Device (this is your actual device)
USB cable to connect to computer
How do I save myself some time:
Download and extract the Javaloader program to a folder of your choosing but remember it for the next steps.
In Windows XP click Start -> Run -> Type CMD and click OK
change your directory to the drive and directory you saved the javaloader program to
(to change drive type x: where x is the drive letter, to change directory type cd\<directoryname>\<subdirectoryname> etc)
Type "javaloader -usb dir >dir.txt" without the quotes (this will generate a list of all programs on your device into a file called dir.txt in the same directory as Javaloader)
Go to the directory with javaloader.exe in Windows Explorer and open the dir.txt file.
The file has a list of a bunch of module names and versions, etc. This is where I can't give you the specific answer to your problem but can provide some guidance.
I only recommend trying to delete 3rd Party applications so look through the list for module names that look like third party apps. You can also sometimes tell 3rd party apps by the version number as well but don't use this as the bible because some RIM apps are not the version of the OS. Once you find some apps you want to try to delete to fix the problem follow the steps below. I recommend you do this one at a time and reset (if the device doesn't automatically reset) between each erase function to narrow down the issue.
Once you find the module to delete go back to the CMD window and type the following:
"javaLoader.exe -usb erase -f <badmodule_name>" where <badmodule_name> is the module you identified to delete which must be typed exactly as it appears in the dir.txt file.
Keep repeating until it reboots successfully.
If this fails follow everyone elses directions to wipe and reload your device but this might just save you some time.
Good luck and post your experience with this fix.