I'm actually surprised that java <package>/class works for you because it shoudl be java <package>
.class, afaik. In order to get this to work from any directory, you need to set your system's CLASSPATH variable. Look at
this page for instructions on how to set this system variable. You just have to set the value to the directory that contains your package. You may also want to add the current working directory (.) to your classpath. The link above should explain what I mean by this. Of course, if you still have questions, let us know.
Keep Coding!
Layne