Haml syntax highlight in Sublime Text 2 for .hamlc templates

Question

I installed the HAML textmate bundle, that display syntax highlight for .haml templates, but I also have Coffee HAML templates that are named like

layout.jst.hamlc

and I would like to add syntax highlight as well.

The Ruby Haml syntax is good enough, so I usually just change the language to Ruby Haml, but then when I close and open the file again, Sublime Text 2 forgets it and I have to assign it again and again.

Is there a way to automatically assign the ruby Haml syntax highlight for .hamlc files?