I have the same problem, buttons get stuck in the on position keeping the teleporters active until one side of my link eventually runs out of energy due to my jumping back and forth. This has led to my client crashing under the stress, getting booted out of a server for moving too fast, and just generally annoying the hell out of me as it makes the teleporter a bit useless.
I'm guessing it is just following the same rules as everything else and quits processing the button/redstone logic as soon as I have teleported out of range. I've had a similar problem with a redstone link from MSFU->reactor getting stuck on (right in the middle of the line of redstone), meaning the reactor never turns back on. This problem also happened right next to my teleporters, so not sure if it is related or is just a general issue with the way MC handles disabling of logic in chunks.
Perhaps if the teleporters could only be activated and used once, and the redstone signal had to turn off and back on before they activated again, this would solve the issue? (or at least avoid it).