As a pacman addict, I have a few comments:
* the teleporters are a really cool addition!
* in the real pacman, the corners of the maze are round which you can use to take corners quicker. I think this is an often overlooked aspect of pacman that really adds to the playability.
* in the real pacman, ghosts never go back the way the came when they reach a corner. Makes the ghosts' behaviour a bit better I think. The ghosts only reverse direction at some 'random' times (and all ghosts will then reverse direction at once).
* movement is not 100% smooth. Looks like the typical 'java applet choppyness'. You might consider full screen exclusive mode in a web start application instead of an applet and although of course I don't know for sure this will solve it, it will probably help :-)
* You know pacman plus? I thought it was kind of cool when sometimes the maze would disappear when you eat a bonus. Maybe an idea to add that?
But all in all, a very fun and very well done pacman clone!