You have wifi?
If so, go into the market and download an app called msl reader and run it. It'll give you your msl code.
Then go into phone and type ##3282# (##data#) select edit mode, put in the msl as the password, select the second menu option on the list (I forget what it is. If it isn't, just try the third or the first). Hit the plus button at the top right and hit... I think it says clear.
It'll restart your phone and then try to activate.
If that doesn't work, go back to a stock rom (search the forum for jmz dedoxed) (remember to flash everything when installing it, including dalvik cache, cache,boot (if you can),system, and data)
After its set up, go to the app drawer, and use activate. That should do it hopefully