Trying to setup DR instance of BES.

Two BES servers, configured identically except for:

SQL server name (MSDE) is different on Prod and DR instances
Physical server names are different on Prod and DR instances
IP's are different so both can be on the network at same time

The following were configured identically:
CAL key
BES Server name
Blackberry database name
Basically, all other options within the BES install

Prod instance: works 100%.
Take Prod instance offline, stopping ALL Blackberry services and SQL service. Copy the two BES database files (BESMgmt.ldf and MESMgmt.mdf) from D:\Program Files\Microsoft SQL Server\MSSQL\Data to the exact same location on the DR box.
DR instance: Fire up the services and the blackberry works sending and receiving mail, but the Blackberry MDS Connection Service starts and then promptly stops. Therefore no internet access on the device.
Can anyone suggest how I can configure BES on the DR instance to allow MDS to work?!
Any help really appreciated!