This is very silmilar to a problem I had just this morning.
I was trying to update my Pearl 8110 but Desktop Manager kept saying the Phones OS was a newer version than the one I was trying to install....which was rubbish. After reinstalling both DM and the OS file several times to get this to work I decided to try the JL Cmder program and sure enough it kept going back to the main screen after i typed "blackberry" on the wipe menu.
Eventually I got the new OS to install by using the alternate procedure:
What to do next if Jl Cmder will not connect and wipe - BlackBerryFAQ
Follow the instructions carefully and it should work...Also make sure the battery is in the phone lol.
UPDATE
After updating the OS on my phone, Desktop Manager was still saying there was no OS file installed. I decided to uninstall DM 4.7 and try 4.6 and guess what? everything is working now. Dodgy 4.7 is