How can I fix the door of my Panasonic NN-T543W Microwave?

I have had a problem with this beastie for a while now. When I pressed the door open button, the door would be released but not fully open until I pulled it. Now the door is closed but pressing the open button does nothing? There is no resistance left to the button and I don't want to force the door open to try the "Rubber Band" remedies suggested by others without first asking if prising the door would do more damage?
Please help???

Colin Robinson
February 2009