Hey all

With my N900, I have 2 Gmail accounts, both working for years.

First account is a googlemail one (old)
second account is a gmail one.

The googlemail one stopped working where as the gmail one was fine.
I solved it by accessing the 2 accounts via POP3 instead of imap. (Set up mail using Other not pre-configured Google Mail)

Doesn't solve the issue, but that's how I got mail back on my phone.
Does everyone who has this problem have an old googlemail email before they migrated to Gmail?

it has nothing (as far as I can tell) to do with the CSSU/CSSU-thumb.