Using bundle exec bash with MRI, I get my usual shell with a 'bundled' environment. On JRuby, the shell appears to work correctly as well, but for some reason I get no prompt whatsoever and Ctrl-C closes the bundled shell. Sample output:

# JRuby
$ /opt/jruby/bin/bundle exec bash
which jruby
/opt/bin/jruby
^C$

# MRI
$ bundle exec bash
[bundled] $ which ruby
/usr/bin/ruby
[bundled] $ ^C
[bundled] $ exit
exit
$

I'm running a Gentoo system with the following versions:

$ jruby -v
jruby 1.7.0.preview1 (ruby-1.9.3-p203) (2012-05-19 00c8c98) (OpenJDK 64-Bit Server VM 1.6.0_24) [linux-amd64-java]
$ jruby -S bundle -v
Bundler version 1.1.4

Unfortunately I don't have any idea what could be causing this problem, therefore I don't know what information might be useful. Of course, don't hesitate to ask for more specifics. Thanks in advance for your time!