Hi just thought I would share something that went wrong for me today with my SGS2 and how I solved it.

Basically, I was using the phone fine, browsing the net and suddenly loads of FC messages came up for Calendar storage, facebook, ebay etc. Random collection of apps! Just before this happened I had noticed an app updated, but I didnt notice which one. K9mail was going mad and kept checking for new mail every 3 seconds! I tried uninstalling K9mail but after multiple reboots it wouldnt uninstall.

I was backing up my apps ready to restore to factory settings and spend an evening resigned to hours if restoring when I found a suggestion somewhere else for a related problem:

Wipe the cache partition.

Boot into recovery (Vol DOWN + Home + Power) and select "Wipe cache partition". Reboot.

It worked a charm for me and has sorted out whatever went bonkers on my phone!!