diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst
index b62148aead1..aabd6410bff 100644
--- a/Doc/library/tarfile.rst
+++ b/Doc/library/tarfile.rst
@@ -140,6 +140,10 @@ Some facts and figures:
       Constant for a :mod:`gzip` compressed tar archive.
 
 
+   .. deprecated:: 2.6
+      The :class:`TarFileCompat` class has been deprecated for removal in Python 3.0.
+
+
 .. exception:: TarError
 
    Base class for all :mod:`tarfile` exceptions.
diff --git a/Lib/tarfile.py b/Lib/tarfile.py
index 619921328ae..85abcd8d850 100644
--- a/Lib/tarfile.py
+++ b/Lib/tarfile.py
@@ -2468,6 +2468,9 @@ class TarFileCompat:
        ZipFile class.
     """
     def __init__(self, file, mode="r", compression=TAR_PLAIN):
+        from warnings import warnpy3k
+        warnpy3k("the TarFileCompat class has been removed in Python 3.0",
+                stacklevel=2)
         if compression == TAR_PLAIN:
             self.tarfile = TarFile.taropen(file, mode)
         elif compression == TAR_GZIPPED:
@@ -2501,10 +2504,10 @@ class TarFileCompat:
         except ImportError:
             from StringIO import StringIO
         import calendar
-        zinfo.name = zinfo.filename
-        zinfo.size = zinfo.file_size
-        zinfo.mtime = calendar.timegm(zinfo.date_time)
-        self.tarfile.addfile(zinfo, StringIO(bytes))
+        tinfo = TarInfo(zinfo.filename)
+        tinfo.size = len(bytes)
+        tinfo.mtime = calendar.timegm(zinfo.date_time)
+        self.tarfile.addfile(tinfo, StringIO(bytes))
     def close(self):
         self.tarfile.close()
 #class TarFileCompat
diff --git a/Misc/NEWS b/Misc/NEWS
index 6db54e0e02c..5824ce3279c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -38,6 +38,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #3039: Fix tarfile.TarFileCompat.writestr() which always
+  raised an AttributeError.
+
 - Issue #2523: Fix quadratic behaviour when read()ing a binary file without
   asking for a specific length.