That always, always means that the class mentioned in the error message is not in the classpath of the application which tried to load it.
If you need help setting your classpath might I suggest having this post moved to the New to Java forum? There's nothing special about POI in this request. Let me know, that topic is discussed very frequently there.
Joined: Mar 22, 2005
I notice that the classpath contains spaces - is it properly quoted wherever necessary?
Apart from that I'd advise to switch to the latest release of POI (3.5) posthaste; it is magnitudes better than some release candidate of 3.0. You'll save yourself a lot of grief.