I am running gummy May 8, 2012 and like everybody else.. bad 4g signals. When i install new rom, 4g is good.. then when i reboot, i lose 4g signals all the time. I reboot the device and go though the motions.. turn GSM, on and off and CDMA, ETC.. anyway, today i decided to just wipe dalvik only and guess what? it work for me. it will update like when you install new gapp. so far, strong 4g signal. I also post this on rootzwiki to help other people out.