It looks as though you have to do this from single user mode prior to boot. The problem here though is I am not totally sure how to do this. There is a guide on here somewhere on using Marvins but it speaks of a patch directory of which I cant find in the marvins app.

As you know though I am in exactly the same situation as you and although I am in SL I can basically only use the browser at the moment so need to patch my patchables.

Good Luck!