I'll never try this application because it's stated to work only with 10.4+ Why on earth should an application that can be replaced with 2 simple shell commands require 10.4 if these functionality is build into OS X since 10.0????

Just have a look at www.hmug.org/man/1/at.php

I could write a beautifull GUI for these tools in under 15 minutes. and this would work perfekt on every OS version.