Can you show us where you define "clsname". Also, as the previous poster mentioned, you need to convert the "." characters to "/" characters, and add a leading "/" character.
Edit:
And another to remember that, that complicates all of this, are internal classes, anonymous and otherwise, that will appear with a "$" character in the name of the class file, so the class file name will not exactly match the name of the class, if it even has one. So if you run into a class that contains internal classes and you wish to "cycle through" these classes as well, you may wind up having some real fun attempting to paste together the name of the class file.
2nd Edit:
Also, I don't believe the problem you are having here is really one for the Advanced forum. But, if the moderators agree with me, this thread will probably be moved to the Intermediate forum anyway.
[ January 12, 2007: Message edited by: Martin Simons ]
[ January 12, 2007: Message edited by: Martin Simons ]