Headphone adapter not working...Any advice?

Hello all, I bought the headphone adapter at the link below:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370352963990&ssPageName=STRK:MEWNX:IT

I got it today, but as soon as I plug it in it starts calling my most recent contact and I can't disconnect from the call until I unplug the adapter. If I bring up the music player first, and then insert the adapter it will not make a phone call, but the music just plays through the phone speakers just like it does without the adapter. I also tried turning the phone off, inserting the adapter, then restarting the phone with the adapter already in, but all I got was a bright green screen and I had to take the battery out to get it back on.

Granted, it's a dirt cheap adapter from China, but the seller seems reputable and I haven't found anyone else complaining of this problem. So, is it the adapter? Is it the phone? Are there any fixes, or should I just try buying a different kind of adapter?

Thanks!

Yes. Whether the head phones are attached or not does not seem to make any difference.

Okay, thanks. I'll give that a try.

If it doesn't work, I'll just buy another one from someone else. They are pretty inexpensive. My main goal is just to get one! I don't have an mp3 player, so one of the main reasons I got this phone was to use it for music...