LoadError: no such file to load with 1.7.10 when using jruby -r

[kares]

this seems to only affect --1.8 mode, all works fine when loaded manually e.g.

kares@sputnik:~/workspace/oss/jruby-rack$ jruby -rubygems -rbundler -S irb
>> exit
kares@sputnik:~/workspace/oss/jruby-rack$ 
kares@sputnik:~/workspace/oss/jruby-rack$ jruby --1.8 -rubygems -rbundler -S irb
LoadError: no such file to load -- bundler
kares@sputnik:~/workspace/oss/jruby-rack$ 
kares@sputnik:~/workspace/oss/jruby-rack$ jruby --1.8 -rubygems -S irb
>> require 'bundler'
=> true
>> exit

p.s. I've looked through previous issues but none of them seemed to handle this case (so I'm not sure if it's fixed on master or the 1_7 branch). it used to work on some 1.7 release, I've tried rubygems version 2.1.11, 2.2.2 and 1.8.29 as well.