thank you. i am trying to get this set up with the blackberry curve 9360 on the o2 UK network using push. o2 have confirmed in an email:

I have spoken to Blackberry Technical and they have advised that the googlemail address is conflicting with the Blackberry Server and it is something on the googlemail end.  They have advised that you will need to contact googlemail regarding this as they will need to check on their servers to solve the issue.
 
I’m sorry that we haven’t been able to resolve it on our end, but we have tried everything possible to solve it and unfortunately it is an issue that is beyond our control.