Just installed Internet Security 5, ran full system scan that included the Mac OSX/Version 10.7.3, and it's "Time Machine". Why is this scan still running after 36 hours? It's up to 16,658,802 of 16.658,802 and stil racing upward.
There's an issue scanning Time Machine volumes due to the way the links are managed for incremental backups. Try disabling scan of that drive, your results should be better.
For the current scan, just cancel. When you do another System scan, just don't choose the Time Machine volume from the list that is presented (if you have no external drives, just select your main hard disk).