Phone connection not the same as 770
 

I have updated from my 770 to an N810 and in general I love it.

When I had the 770 I couldn't connect to the internet through my phone originally, so assumed it was some kind of operator block, but then I found an Web page listing exactly the problem - connecting a nokia n73 with a 770 on Three. Followed the instructions and everything has worked since.
I assumed with the 810 it would be the same - the dialog boxes are. I set it up exactly the same but it just says the unhelpful 'connection error'.
I can see by the phone status it connects to the phone and tries to connect, and going through the 770 and 810 dialog I can compare that they are both identically set up, but the 770 works and the 810 doesn't.

Anyone have any clue either why it doesn't work or if I can find out what is going wrong with the 810?