We are using Nokia e63's at our site as they worked well for us with GMS.

We have the Data Sync server installed and all appears to be working fine, but the E63s only behave if we run unsecured. When we use secure sync seems to stop half way and email push never happens.

We are using Mail for Exchange version 3.00.073 and Novell Data Sync version 183, we are using a commercial certificate and the phone has not complain about it at any stage, of note it is a wildcard certificate in case that makes any difference.