An NPC from The World of Restenford
He wears the uniform of the Restenford Regiment, not the KGB (I may have misled you on this one).
He was part of the previous adventure that went back to Cragson Mines (traveling as the ranger Jason). When you get a little curious about the difference in names, you find out his name is Jason Jockomo (or Jason of the house of Jockomo).
Only D'Wal knows Jason Jockomo as Jetero/Jasmalus (of the KGB), and he can't talk about it (the other characters from that adventure are no longer active).