Found the solution.The PHP/MapScript documentation says the projection parameters should be comma-delimited, but apparently the projection can be specified in the standard PROJ.4 format: $projIn = ms_newProjectionObj("+proj=tmerc +lat_0=0 +lon_0=27 +k=1 +x_0=3500000 +y_0=0 +towgs84=-75,-230,-89 +ellps=intl");
Now the coordinate transformation works as intended. Robert
