Running GMS 14.2.1 build 289 as a VM on SLES11sp3 and GW 14.2.1

The user has an iPhone with the latest IOS. His calendar does a sync but not the mail. So, new mail arrives on his PC but does not appear on his phone. The user then opens the mail on the PC and then the iPhone syncs and shows the opened mail. It is as if the opening of the mail on the PC triggers the sync to the phone.

Have restarted GMS, removed and re-added the user on the GMS server. Removed and re-configured the exchange account on the iPhone, but still no joy!

Any ideas....