exclude javascript from theme files

Is there an option to exclude the rpx javascript from theme files? E.g. I just want to use it on the wp-login form, and would like to reduce the heavy external javascript footprint on the frontend.

There are some options to do that like : http://wordpress.stackexchange.com/questions/12863/check-if-were-on-the-wp-login-page

but what i’d like to know is if that’s built in already, e.g. an advanced option checkbox that when set, would only include RPX/Engage on the login pages and administration, but not the frontend

cheers

http://wordpress.org/plugins/rpx/