Redmine

It's not possible to use JRuby 1.7.2 with current trunk of redmine (2.3?) because of a rake error message.

I'm able to reproduce the error by downloading a vanilla JRuby 1.7.2 + redmine trunk (from GitHub), execute a bundle install and then rake generate_secret_token (or a warble config for WAR creation). This gives:

ArgumentError: regexp prepocess failed: too short control escape
Backtrace at C:/[...]jruby/lib/ruby/gems/shared/gems/rake-10.0.3/lib/rake/backtrace.rb:10
Rake at C:/[...]jruby/lib/ruby/gems/shared/gems/rake-10.0.3/lib/rake/backtrace.rb:2
(root) at C:/[...]jruby/lib/ruby/gems/shared/gems/rake-10.0.3/lib/rake/backtrace.rb:1
[...]

The backtrace.rb file contains the line:
SUPPRESS_PATTERN = %r!(\A#{SUPPRESSED_PATHS.join('|')}|bin/rake:\d+)!i

Deleting this line and rake or warble isn't throwing the error.

I also had this error with JRuby 1.6 and redmine >= 2.2.0. I'm using Windows 7 64bit. List of installed gems attached.