diff --git a/WHATSNEW b/WHATSNEW
index a0cafee24..75010cf3a 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -388,6 +388,10 @@ Fixed bugs:
  * <loadproperties>' encoding attribute didn't work.
    Bugzilla Report 47382.
 
+ * Ant created tar archives could contain random bytes at the end
+   which confused some untar implementations.
+   Bugzilla Report 47421.
+
 Other changes:
 --------------
  * A HostInfo task was added performing information on hosts, including info on 
diff --git a/src/main/org/apache/tools/tar/TarBuffer.java b/src/main/org/apache/tools/tar/TarBuffer.java
index 528bc330f..fa619fb03 100644
--- a/src/main/org/apache/tools/tar/TarBuffer.java
+++ b/src/main/org/apache/tools/tar/TarBuffer.java
@@ -412,6 +412,7 @@ public class TarBuffer {
 
         currRecIdx = 0;
         currBlkIdx++;
+        Arrays.fill(blockBuffer, (byte) 0);
     }
 
     /**