The Collaborative International Dictionary of English v.0.48:

jimmy \jim"my\, v. t. [imp. & p. p. jimmied; p. pr. & vb. n.
   jimmying.]
   To pry open (a door, window, etc.) with a jimmy or similar
   device; often used with open; as, the burglar jimmied open
   the back door and stole the TV set.
   [PJC]