Pass cmd through /bin/sh to set default /Users/joe/.rvm/gems/ruby-1.9.3-p392@pro-dev/bin /Users/joe/.rvm/gems/ruby-1.9.3-p392@global/bin /Users/joe/.rvm/rubies/ruby-1.9.3-p392/bin /Users/joe/.rvm/bin /usr/local/sbin /usr/local/bin /usr/bin /bin /usr/sbin /sbin /usr/X11/bin /opt/bin /opt/X11/bin. CMD and native payloads now working.