Um, I don't know about you, but my mods can log into Mod CP, Search for the user, and click "change signature."
They'd have to log into Mod CP, not Admin CP.
(I don't remember this being an add-on, mod, or any special coding.)
I know mods can login to modcp to edit sigs, i don't want to give htacess to mods either thats why I asked about this, as the majority of mod tools now are there without logging into modcp, hence the question about sig edits