Index: src/main/java/hudson/plugins/cobertura/CoberturaBuildAction.java
===================================================================
--- src/main/java/hudson/plugins/cobertura/CoberturaBuildAction.java	(revision 17029)
+++ src/main/java/hudson/plugins/cobertura/CoberturaBuildAction.java	(working copy)
@@ -96,10 +96,12 @@
 			for (Map.Entry<CoverageMetric, Integer> e : scores.entrySet()) {
 		                minKey = e.getKey();
 		        }
-            		localizedDescription = Messages._CoberturaBuildAction_description(result.get(minKey).getPercentage(),result.get(minKey).toString(),minKey.getName());
-		        health = new HealthReport(minValue, localizedDescription);
-            		return health;
-
+			if(minKey != null) {
+            		    localizedDescription = Messages._CoberturaBuildAction_description(result.get(minKey).getPercentage(),result.get(minKey).toString(),minKey.getName());
+            		    health = new HealthReport(minValue, localizedDescription);
+            		    return health;
+			}
+			return null;
 		}
 		
 	}else{
Index: src/main/java/hudson/plugins/cobertura/CoberturaPublisher.java
===================================================================
--- src/main/java/hudson/plugins/cobertura/CoberturaPublisher.java	(revision 17029)
+++ src/main/java/hudson/plugins/cobertura/CoberturaPublisher.java	(working copy)
@@ -200,8 +200,9 @@
      */
     @Override
     public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
-        if (!Result.SUCCESS.equals(build.getResult())) {
-            listener.getLogger().println("Skipping Cobertura coverage report as build was not successful...");
+        Result threshold = onlyStable ? Result.SUCCESS : Result.UNSTABLE;
+        if(build.getResult().isWorseThan(threshold)) {
+            listener.getLogger().println("Skipping Cobertura coverage report as build was not " + threshold.toString() + " or better ...");
             return true;
         }
         listener.getLogger().println("Publishing Cobertura coverage report...");