diff --git a/src/main/java/de/javawi/jstun/attribute/UnknownAttribute.java b/src/main/java/de/javawi/jstun/attribute/UnknownAttribute.java
index 04f1abb..045bbc1 100644
--- a/src/main/java/de/javawi/jstun/attribute/UnknownAttribute.java
+++ b/src/main/java/de/javawi/jstun/attribute/UnknownAttribute.java
@@ -59,7 +59,7 @@ public byte[] getBytes() throws UtilityException {
 		}
 		// padding
 		if (unkown.size()%2 == 1) {
-			System.arraycopy(Utility.integerToTwoBytes(typeToInteger(unkown.elementAt(1))), 0, result, 4, 2);
+			System.arraycopy(Utility.integerToTwoBytes(typeToInteger(unkown.lastElement())), 0, result, 4, 2);
 		}
 		return result;
 	}