I guess SmartOS reserves /usr for the Solaris base install and puts additions in /opt/local. If you look at http://wiki.joyent.com/display/jpc2/SmartOS+Smartmac

I guess SmartOS reserves /usr for the Solaris base install and puts additions in /opt/local. If you look at http://wiki.joyent.com/display/jpc2/SmartOS+Smartmachine+Datasets http://wiki.joyent.com/display/jpc2/SmartOS+Smartmachine+Dat... and click "to see list of installed software", it includes grep 2.5.3.