diff --git a/appengine/src/com/google/android/chrometophone/server/RegisterServlet.java b/appengine/src/com/google/android/chrometophone/server/RegisterServlet.java
index e16c5d3..f796234 100644
--- a/appengine/src/com/google/android/chrometophone/server/RegisterServlet.java
+++ b/appengine/src/com/google/android/chrometophone/server/RegisterServlet.java
@@ -97,9 +97,10 @@ public class RegisterServlet extends HttpServlet {
         }
 
         String deviceRegistrationId = req.getParameter("devregid");
-        if (deviceRegistrationId == null) {
+        if (deviceRegistrationId == null || "".equals(deviceRegistrationId.trim())) {
             resp.setStatus(400);
             resp.getWriter().println(ERROR_STATUS + "(Must specify devregid)");
+            log.severe("Missing registration id ");
             return;
         }