Thank you all for your replies. Very much appreciated. we are under considerable pressure to enhance our Proj4 based apps to include support for epoch. We will see if we can coordinate something via OGP. -- View this message in context: http://osgeo-org.1560.x6.nabble.com/Proj4-and-Epoch-tp5254986p5255859.html Sent from the PROJ.4 mailing list archive at Nabble.com.