take and separate the wall adaptor, and cut the cord about 6 inches to a foot from the plug(or right where its broken) and rewire the unbroken segment, then you can also make the cord as long as you want it. make sure to use the right size wire, radio shack can help you find the right kind.
I've done this to several chargers ive broken, and it works every time, for some of them i ended up using heavy gauge stereo speaker wire, some of them are so low power it didnt matter.