Any way to have traps remote activated?

[Jigokuro]

I'm thinking of a situation where the dungeon if being observed by its own inhabitant with scrying and he can activate the various traps from where he is rather than just when they are walked into. Probably motivated to do this after some canny adventures nullified most every trap with a few cheap donkeys or SMI'd monkeys.
Is there a RAW way to do this? In one situation I'm DM and can just say so, though I'd rather not have to. However there is another where it is similarly relevant where I'm a PC and so it needs to be a RAW declaration (or at least extrapolation.)

[TuggyNE]

Have small hard-to-detect critters scattered around at the manual triggers for traps; when your greater scrying shows that your targets are nearby, cast message through to the trigger beastie and have it spring the trap.

Has the further advantage of ensuring that traps often/always have some covering fire to make it more difficult to disable at leisure.

[VeisuItaTyhjyys]

Just have the trap activated by a fairly routine method from a great distance; a pressure plate that sets off a comically byzantine Rube Goldberg machine in the dungeon walls which, in turn, activates the trap, for instance.