Are you running 10.2.3? I searched my system for this file and do not have it, however i have not installed norton either. .kext files are system extensions usually kept in the System/Library/Extensions folder. I would suggest that you search your system for this file and see if you find it. If you do find it (I'll warn you i'm not entirely sure you should mess with stuff inside the System folder) Try removing it, it may take either sudo user command line or logging in as root to do it.
