Was lookin for a way to update EI22 to EL30 on the Epic 4g on a rooted phone. Since I had the ACS CWM recovery already installed, I found this zip here that has a pre-rooted EL30 stock kernel HERE
Now in about phone I see it's running EL30. But the modem is still on EI22. No problem, they have another zip here --> HERE that allows you to update the modem firmware.
All done and cool! Thanks!
On a rooted phone, my fav app is :
Wifi tether - http://code.google.com/p/android-wifi-tether/
Quick Boot - android market