Index: /branches/eam_branch_20071023/psastro/src/psastroMosaicSetMatch.c
===================================================================
--- /branches/eam_branch_20071023/psastro/src/psastroMosaicSetMatch.c	(revision 15521)
+++ /branches/eam_branch_20071023/psastro/src/psastroMosaicSetMatch.c	(revision 15522)
@@ -15,6 +15,15 @@
     if (!status) { 
 	psError(PS_ERR_IO, false, "Failed to lookup matching radius: %s", radiusWord); 
-	return NULL; 
+	return false; 
     } 
+
+    if (RADIUS <= 0.0) {
+	if (iteration == 0) {
+	    psError(PS_ERR_IO, false, "Invalid match radius for first iteration: %s", radiusWord); 
+	    return false; 
+	} 
+	psWarning ("skipping match for iteration %d\n", iteration);
+	return true;
+    }
 
     // this loop selects the matched stars for all chips