Ok, just figured i would play around and this is what i found. After you have went to 3.1 DO NOT try to lock your xoom back. If you have 3.1 images, even if you wipe it will softbrick. The only way i was able to relock was to reflash the stock 3.0.1 images, wipe and then fastboot oem lock. AGAIN DO NOT TRY TO OEM LOCK 3.1.