|There is a virus that hides as both lsass and isass. With an ell or an eye, by the way.|
Read up on MS page on how to do a repair by booting to the xp cd.
It is also possible to do other ways maybe. A live cd to boot to restore point or even copy a new lsass.exe.
I support the 'Everybody Draw Mohammed Day'. A religion doesn't deny my freedom.