diff --git a/projects/samskivert/src/java/com/samskivert/util/KeyUtil.java b/projects/samskivert/src/java/com/samskivert/util/KeyUtil.java
index 4e8ac9c8..c70a7206 100644
--- a/projects/samskivert/src/java/com/samskivert/util/KeyUtil.java
+++ b/projects/samskivert/src/java/com/samskivert/util/KeyUtil.java
@@ -58,7 +58,7 @@ public class KeyUtil
     public static boolean verifyLuhn (String key)
     {
         // If there is a non digit, or it is all zeros.
-        if (key.matches("\\D") || key.matches("^[0]+$")) {
+        if (StringUtil.blank(key) || key.matches("\\D") || key.matches("^[0]+$")) {
             return false;
         }