How to delete One line on tcsh history....??

[Agus]

Hi guys,

I've been trying to delete one line from my user tcsh history cause i made a
su and it seems didnt hit enter very well so i typed the password on the
console...Now anyone that can look my history will see my pass...

I tried to edit and delete a few lines but it all comes again....tried
history clear but when i login again it apperas all again..hehe...
Its so secure and cool tcsh taht i have no idea how to do it...been a bash
user...

Cheers and thanks,
Agustin