diff --git a/tools/cooja/java/se/sics/cooja/plugins/analyzers/PcapExporter.java b/tools/cooja/java/se/sics/cooja/plugins/analyzers/PcapExporter.java
index f978bbb60..4dbbe12f4 100644
--- a/tools/cooja/java/se/sics/cooja/plugins/analyzers/PcapExporter.java
+++ b/tools/cooja/java/se/sics/cooja/plugins/analyzers/PcapExporter.java
@@ -39,7 +39,7 @@ public class PcapExporter {
             out.writeInt((int) System.currentTimeMillis() / 1000);
             out.writeInt((int) ((System.currentTimeMillis() % 1000) * 1000));
             out.writeInt(data.length);
-            out.writeInt(data.length);
+            out.writeInt(data.length+2);
             /* and the data */
             out.write(data);
             out.flush();