Index: /issm/trunk-jpl/src/c/modules/CoordinateSystemTransformx/CoordinateSystemTransformx.cpp
===================================================================
--- /issm/trunk-jpl/src/c/modules/CoordinateSystemTransformx/CoordinateSystemTransformx.cpp	(revision 26414)
+++ /issm/trunk-jpl/src/c/modules/CoordinateSystemTransformx/CoordinateSystemTransformx.cpp	(revision 26415)
@@ -4,23 +4,17 @@
 
 /*Header files*/
-#include <proj.h>
-
 #include "./CoordinateSystemTransformx.h"
 #include "../../shared/shared.h"
 #include "../../toolkits/toolkits.h"
+#include <proj.h>
 
 void CoordinateSystemTransformx(double** px_dest,double** py_dest,double* x_src,double* y_src,int size,const char* str_src,const char* str_dst){
 
 /*
-	NOTE:
-	- Compilation of this module is fenced in Makefile.am, so we do not 
-	have to check again if _HAVE_PROJ_ is defined
-	- As of at least PROJ 8, version macros are defined,
-
-		https://proj.org/development/reference/macros.html
+NOTE:
+- Compilation of this module is fenced in Makefile.am, so we do not have to 
+check again if _HAVE_PROJ_ is defined
 */
-#if !defined(PROJ_VERSION_MAJOR) || !PROJ_AT_LEAST_VERSION(8, 0, 0)
-	_error_("PROJ major version >= 8 required");
-#else
+#if defined(PROJ_VERSION_MAJOR) && PROJ_VERSION_MAJOR >= 6
 	/*
 	Converts an array of longitude (x_src) and array of latitude (y_src) in the 
@@ -76,4 +70,6 @@
 	*px_dest=x_dest;
 	*py_dest=y_dest;
+#else
+	_error_("PROJ version >= 6 required");
 #endif
 }
Index: /issm/trunk-jpl/src/wrappers/CoordTransform/CoordTransform.cpp
===================================================================
--- /issm/trunk-jpl/src/wrappers/CoordTransform/CoordTransform.cpp	(revision 26414)
+++ /issm/trunk-jpl/src/wrappers/CoordTransform/CoordTransform.cpp	(revision 26415)
@@ -4,19 +4,13 @@
 
 /*Header files*/
+#include "./CoordTransform.h"
 #include <proj.h>
 
-#include "./CoordTransform.h"
-
 /*
-	NOTE:
-	- Compilation of this module is fenced in Makefile.am, so we do not 
-	have to check again if _HAVE_PROJ_ is defined
-	- As of at least PROJ 8, version macros are defined,
-
-		https://proj.org/development/reference/macros.html
+NOTE:
+- Compilation of this module is fenced in Makefile.am, so we do not have to 
+check again if _HAVE_PROJ_ is defined
 */
-#if !defined(PROJ_VERSION_MAJOR) || !PROJ_AT_LEAST_VERSION(8, 0, 0)
-	_error_("PROJ major version >= 8 required");
-#else
+#if defined(PROJ_VERSION_MAJOR) && PROJ_VERSION_MAJOR >= 6
 	/*
 	Converts an array of longitude (x_src) and array of latitude (y_src) in the 
@@ -108,4 +102,5 @@
 		MODULEEND();
 	}
-
+#else
+	_error_("PROJ version >= 6 required");
 #endif
Index: /issm/trunk-jpl/src/wrappers/matlab/Makefile.am
===================================================================
--- /issm/trunk-jpl/src/wrappers/matlab/Makefile.am	(revision 26414)
+++ /issm/trunk-jpl/src/wrappers/matlab/Makefile.am	(revision 26415)
@@ -194,6 +194,8 @@
 ContourToNodes_matlab_la_LIBADD = ${deps}
 
+if PROJ
 CoordTransform_matlab_la_SOURCES = ../CoordTransform/CoordTransform.cpp
 CoordTransform_matlab_la_LIBADD = ${deps}
+endif
 
 DistanceToMaskBoundary_matlab_la_SOURCES = ../DistanceToMaskBoundary/DistanceToMaskBoundary.cpp