there have been alot of threads about this lately... info is accessible by clicking on the the lil tab above that says "search this forum" and try searching for,oh,maybe PB31IMG
but in a nutshell:
-go to
Inc. Recoveries | doug piston
-download the 2.5.1.2 version
-make sure your sd card is formatted FAT 32
-rename the recovery file you downloaded "PB31IMG" and move it to the root of your sd card(if youre on a windows machine it will automatically add ".zip". if your not, the file must be named "PB31IMG.zip" exactly)
-power phone off.
-enter hboot by holding vol down while powering on.
-wait a couple seconds. the phone will find the PB31IMG file and ask you if you want to update. tell it yes.
-when its done,you have clockwork 2.5.1.2
ignore what rom manager says is your current recovery. it is confused
delete the PB31IMG file from your sd card to avoid being asked to update every time you enter hboot.
some more info on this thread
http://androidforums.com/incredible-all-things-root/263696-pretty-sure-i-just-killed-my-phone.html