MacBook Pro :: (Early 2008) Unresponsive Trackpad Button Not Register Click

I've noticed that when I try clicking on the trackpad's button, most of the time it will register the press and other times it doesn't. The button, physically, doesn't feel any different whether it registers the click or not. The button "clicks" down like normal and doesn't feel loose. Also, when I click and hold on the button and try to move my finger around the trackpad to highlight text or drag a folder, most of the time, the computer acts like I let go of the button and pressed it down again multiple times. While it does this, my finger remains on the trackpad button without being lifted. I recently upgraded my Mac to Snow Leopard but the problem occurred even with Leopard installed. I'm unsure as to whether or not this is a software or hardware issue. Could it be that there's something lodged under the trackpad button to cause this? If so, how would I be able to check under the button?