RIM painstakingly writes in every documentations and articles you could get, but mistakes are still made... "Perform the following tasks using the account that was used to install the BlackBerry Enterprise Server software unless otherwise stated"... blah blah blah...
Awalys use the same service account that you first installed your BES, you will never go wrong. If you are using Windows authentication, your SQL DBA had already granted you the necessary SQL permissions to start off. Problems come when you use a difference service account and then SQL just block you, why? You don't have the bloody permissions!
Native but 4th class citizen of a nation governed by idiots who import congestions & contention.