Like I'm sure you already know, there are always constant issues with facebook. My suggestion is making sure that you have the latest software on your blackberry device. Make sure that you do an advance backup (before updating software) of your info using the desktop manager and re-install the FB app if you still want to have access to facebook. The advance backup lets you select what info you want to back up instead of backing all the info in the device that might have corrupt files.
I'm doing research on this, when I find a resolution I'll make sure to let you know.