That warning was bothering me enough that I ended up forking jquery-rails simply to drop in 1.11.beta3. Until jquery-rails gets updated (doesn't appear to be at the time of writing) this is an easy one liner:

gem 'jquery-rails', github: 'onpaws/jquery-rails'

Shame; kinda gotten used to it ;)

Bummer, bootstrap still causes the same issue, which can be seen on twitter.com.

its about time!