--- MITgcm/model/src/dynamics.F	2005/09/11 20:52:09	1.124
+++ MITgcm/model/src/dynamics.F	2005/09/16 21:40:58	1.125
@@ -1,8 +1,9 @@
-C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/model/src/dynamics.F,v 1.124 2005/09/11 20:52:09 jmc Exp $
+C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/model/src/dynamics.F,v 1.125 2005/09/16 21:40:58 jmc Exp $
 C $Name:  $
 
 #include "PACKAGES_CONFIG.h"
 #include "CPP_OPTIONS.h"
+#undef DYNAMICS_GUGV_EXCH_CHECK
 
 CBOP
 C     !ROUTINE: DYNAMICS
@@ -549,6 +550,15 @@
       ENDIF
 #endif
 
+#ifdef DYNAMICS_GUGV_EXCH_CHECK
+C- jmc: For safety checking only: This Exchange here should not change 
+C       the solution. If solution changes, it means something is wrong, 
+C       but it does not mean that it is less wrong with this exchange.
+      IF ( debugLevel .GT. debLevB ) THEN
+       CALL EXCH_UV_XYZ_RL(gU,gV,.TRUE.,myThid)
+      ENDIF
+#endif
+
 #ifdef ALLOW_DEBUG
       IF ( debugLevel .GE. debLevB )
      &   CALL DEBUG_LEAVE( 'DYNAMICS', myThid )