I personally know that jedi with Healer powers can remove a DOT off a weapon that is on a wall. One of my friends did it to a POS Dotted stone knife I had on the floor. He promptly went to the guild hall of our enemy and proceeded to remove the DOTs off the weapons they had on display.
He uses /forcecurepoison or /forcecure disease depending on what kinda dot it is.
Tested it with a crappy Nightsister Lance, had 8000 charges before the heal, no dot after.