diff --git a/srv/scripts/gvm b/srv/scripts/gvm
index 2f8bccb9..de952af5 100755
--- a/srv/scripts/gvm
+++ b/srv/scripts/gvm
@@ -35,7 +35,7 @@ function determine_candidate_version {
 
 	if [ "$VERSION" == "invalid" ]; then
 		echo ""
-		echo "Stop! $1 is not a valid grails version."
+		echo "Stop! $1 is not a valid $CANDIDATE version."
 		exit 0
 	fi
 }
diff --git a/srv/server.groovy b/srv/server.groovy
index c1463b08..754cb2c7 100644
--- a/srv/server.groovy
+++ b/srv/server.groovy
@@ -41,13 +41,13 @@ rm.get("/candidates/:candidate") { req ->
 	def candidate = req.params['candidate']
 	def versions = buildCsv(candidates[candidate])?.toString()
 	addPlainTextHeader req
-    req.response.end (versions ?: "")
+    req.response.end (versions ?: "invalid")
 }
 
 rm.get("/candidates/:candidate/default") { req ->
 	def candidate = req.params['candidate']
 	addPlainTextHeader req
-	req.response.end defaults[candidate]
+	req.response.end (defaults[candidate] ?: "")
 }
 
 rm.get("/candidates/:candidate/list") { req ->