Mootools is Conflicting with Another Script.

I have created a product drop down menu (as seen here in the content area: http://wernermntest.vmind.com/index.php?id=127) that uses javascript to minimize and maximize product categories. This menu works perfect on the default MODx template.

My problem is that as soon as I tie this drop down menu into my website template that uses the mootools library, the menu no longer works correctly. I have tried removing mootools from the template temporarily and it functions perfectly. Here is a link to the problem page: http://wernermntest.vmind.com/index.php?id=61

Does anyone have an idea why mootools is interfering with other scripts on my page?

I don’t know why it conflicts but why not use one of the accordion type scripts that are based on mootools?
It’ll be easier in the end