Index: graph/src/main/java/org/apache/hama/graph/GraphJobRunner.java =================================================================== --- graph/src/main/java/org/apache/hama/graph/GraphJobRunner.java (revision 1572571) +++ graph/src/main/java/org/apache/hama/graph/GraphJobRunner.java (working copy) @@ -296,8 +296,9 @@ if (conf.getBoolean("hama.check.missing.vertex", true)) { if (comparision < 0) { throw new IllegalArgumentException( - "Messages must never be behind the vertex in ID! Current Message ID: " - + firstMessageId + " vs. " + vertex.getVertexID()); + "A message has recieved with a destination ID: " + firstMessageId + + " that does not exist! (Vertex iterator is at" + vertex.getVertexID() + + " ID)"); } } else { while (comparision < 0) {