The issue started because I was trying to port over Raj Kaimal's ( http://weblogs.asp.net/rajbk/ ) GridView client side reordering extender to the Data Grid. Since both controls are very similar the work wasn't difficult, however I was getting hung up trying to stick the .js file in my backend dll.
Searching google it seemed as though a lot of people got hung up in this area. I finally stumbed on Lee's post which directed me to Damian's blog
While niether of those posts directly solved my issue, Damian gave me the idea of using a reflector to see what the .NET view of my dll looked like. From that and a little luck I discovered that the proper syntax was:
then for the script reference:
new ScriptReference("[default namespace].[folder].[file name].js", "[assembly name]");
most people keep the default namespace and the assembly name the same which makes things simpler but fosters a lot of confusion as to what the various parameters are really looking for.