diff --git a/mutants/mutant-5/swen90006/machine/Machine.java b/mutants/mutant-5/swen90006/machine/Machine.java
index 9fc13d5b8bc610f6f1f57c2e6291be343e71f353..a56907ab061d2c2cdfa9b43385b06b0bcd136701 100644
--- a/mutants/mutant-5/swen90006/machine/Machine.java
+++ b/mutants/mutant-5/swen90006/machine/Machine.java
@@ -148,7 +148,7 @@ public class Machine
   private void validate_offset(int offset)
     throws InvalidInstructionException
   {
-    if (offset < -MAX_ADDR || offset > MAX_ADDR) {
+    if (offset < -MAX_ADDR || offset >= MAX_ADDR) {
       throw new InvalidInstructionException();
     }
   }
@@ -266,7 +266,7 @@ public class Machine
 	  throw new InvalidInstructionException();
 	}
 	int offs = parseOffset(toks[1]);
-	pc  = pc + offs+1;
+	pc  = pc + offs;
 	count++;
 	continue; /* avoid default increment of pc below */
       } else if (toks[0].equals(INSTRUCTION_JZ)){