I activated the plugin and got this warning:
The plugin generated 1 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.
I was able to find the source of the problem, a tab character after the ?> at the bottom of the adminPages_class.php file. I guess that's why many PHP devs (myself included) like to leave out the closing PHP tag, except in template files. :-)