erb in coffee script with rails 3.1

I would like to use some erb in my .coffee files, like the following example

myLatlng: new google.maps.LatLng(<%=@location.latitude %>, <%=@location.longitude %>)

I renamed my locations.js.coffee to locations.erb.coffee

but I still get the following error

Error compiling asset application.js:
ExecJS::ProgramError: Error: Parse error on line 4: Unexpected 'COMPARE'
  (in /Users/denisjacquemin/Documents/code/projects/geolog/app/assets/javascripts/locations.erb.coffee)
Served asset /application.js - 500 Internal Server Error