title: Postgis install - configure does not recognize GEOS version
body: <p>I am installing PostGIS on Ubuntu 13.04.  I have installed GEOS 3.3.8.  I have downloaded and opened postgis, and when I do ./configure it says that I need a GEOS >=3.1. Which I thought I had.  I am running configure with --with-geos-config=/home/geos-3.3.8/(etc), pointing to the version of geos I just installed. 
  Why is it not finding the version I have? </p>