id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,cpu,platform 1988,towgs84 datum transform options not maintained with shapefile export,voncasec,grass-dev@…,"Perhaps this issue is related to the GDAL ticket 4345 (http://trac.osgeo.org/gdal/ticket/4345). Including it here in case GRASS handles the data differently. In general, if I am using a projection defined with towgs84 datum transform parameters and I want to export the layer to a shapefile, the +towgs84 datum transform parameters are not included. Often times, I will just manually modify the .prj file after the fact to include the TOWGS84 flag to ensure that there is no shift when viewing the locations in a GIS that allow for on the fly reprojections. Example of g.proj -e GRASS 6.4.3svn (Bayaguana_NAD27_Caribbean):/usr/local/grass-6.4.3svn/etc > g.proj -e PROJCS[""UTM_Zone_19_Northern_Hemisphere"", GEOGCS[""GCS_clark66"", DATUM[""D_North_American_1927"", SPHEROID[""Clarke_1866"",6378206.4,294.9786982]], PRIMEM[""Greenwich"",0], UNIT[""Degree"",0.017453292519943295]], PROJECTION[""Transverse_Mercator""], PARAMETER[""latitude_of_origin"",0], PARAMETER[""central_meridian"",-69], PARAMETER[""scale_factor"",0.9996], PARAMETER[""false_easting"",500000], PARAMETER[""false_northing"",0], UNIT[""Meter"",1]] Desired output of g.proj -e + .prj file from v.out.ogr GRASS 6.4.3svn (Bayaguana_NAD27_Caribbean):/usr/local/grass-6.4.3svn/etc > g.proj -e PROJCS[""UTM_Zone_19_Northern_Hemisphere"", GEOGCS[""GCS_clark66"", DATUM[""D_North_American_1927"", SPHEROID[""Clarke_1866"",6378206.4,294.9786982], TOWGS84[-3.0,142.0,183.0,0,0,0,0]], PRIMEM[""Greenwich"",0], UNIT[""Degree"",0.017453292519943295]], PROJECTION[""Transverse_Mercator""], PARAMETER[""latitude_of_origin"",0], PARAMETER[""central_meridian"",-69], PARAMETER[""scale_factor"",0.9996], PARAMETER[""false_easting"",500000], PARAMETER[""false_northing"",0], UNIT[""Meter"",1]] ",defect,closed,normal,7.0.5,Projections/Datums,svn-releasebranch70,worksforme,"g.proj, v.out.ogr",,x86-64,Linux