Jruby - (LoadError) no such file to load
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I have a shell integrated in the web interface. 
5 days ago it was working but now I receive this error [1] even though I did not modify the sources.
I asked a friend to get the same sources and he did not receive any errors.
Do you know what could be the problem?

[1] 

        javax.script.ScriptException: org.jruby.exceptions.RaiseException: (LoadError) no such file 
    to load -- hirb