This worked for me! I don't know if this will work for everyone, but it's definitely worth a shot. The link will explain what to do, but I just shut down my 1525, unplugged it, took the battery out, pushed the power button about 5 or 6 times, and put it back together. And my mouse is good as new! (but with Dell sometimes new isn't even That great! but it works so I won't complain)
Thanks for the link!