Easy fix, either cut off the jack and install a new 1/4" TRS jack and wire the jack (tip and ring) the other way around OR open the switch box and do it there... if you can solder, or know someone who can, it will take 15-30mins.
Cheers
Matt
it SUX hey! i got the same amp (by the way this was the best investment i EVER made, it takes pedals EXTREMELY well!) i got a VOX footswitch 2 channel, it works perfectly, think i paid R250. Only problem is that its the opposite way around(i think on the peavey's side) so 1st switch = reverb, 2nd switch = channel select.
enjoy the amp, its a BEAUTY!