Has anyone been able to use nokia mail for exchange on a Nokia E5?

I set up the account as normal and it will do the first sync, then receive each new email but cannot reply or send a new email.

No errors on the server, and the phone just pops ups "email not sent"

Nokia support are investigating the problem but have no

we sync many other phone models to zimbra but this E5 fails

tried another E5 and that has same problem

Any ideas?