And your company has a BES server? Don't you have a BES administrator?
Here is the link to the RIM Java developer resource site:
http://supportforums.blackberry.com/...java_dev%40tkb
Anyway, if your app uses "restricted" API's, then it must be signed. This is just common-sense security. Your developer should know this, and he should have signed the build after he completed it.
This brings me to yet another issue: if the app is not signed, then it was apparently never tested on a device. Are you sure you want to push it to your company's users?
Just some friendly advice: stop and re-evaluate what you are doing here. If your developer didn't have the sense to sign & test the app, get someone else to take a look at it.