Index: /issm/trunk-jpl/src/m/classes/clusters/generic.m
===================================================================
--- /issm/trunk-jpl/src/m/classes/clusters/generic.m	(revision 12755)
+++ /issm/trunk-jpl/src/m/classes/clusters/generic.m	(revision 12756)
@@ -55,5 +55,5 @@
 			end
 			if isnan(cluster.np),
-				checkessage('number of processors should not be NaN!');
+				md = checkmessage(md,'number of processors should not be NaN!');
 			end
 		end