onclick code disappears in template

I have a jumpmenugo and the corresponding javascript saved as a library item.
It includes the following after the list of options
<input type="button" name="Button1" value="Go"
onClick="MM_jumpMenuGo('menu1','parent',0)" class="jumpmenu">

When I preview it in a browser, all list values work.

However, when I insert the library item into a template, the onClick code
drops out as follows
<input type="button" name="Button1" value="Go" onClick="" class="jumpmenu">

How do I solve this?