diff --git a/modules/system/system.tar.inc b/modules/system/system.tar.inc
index 32bf7f0..8c8a024 100644
--- a/modules/system/system.tar.inc
+++ b/modules/system/system.tar.inc
@@ -88,17 +88,22 @@ class Archive_Tar // extends PEAR
 
     // {{{ constructor
     /**
-    * Archive_Tar Class constructor. This flavour of the constructor only
-    * declare a new Archive_Tar object, identifying it by the name of the
-    * tar file.
-    * If the compress argument is set the tar will be read or created as a
-    * gzip or bz2 compressed TAR file.
+    * Returns a new Archive_Tar object.
     *
-    * @param    string  $p_tarname  The name of the tar archive to create
-    * @param    string  $p_compress can be null, 'gz' or 'bz2'. This
-    *                   parameter indicates if gzip or bz2 compression
-    *                   is required.  For compatibility reason the
-    *                   boolean value 'true' means 'gz'.
+    * This flavour of the constructor only declares a new Archive_Tar object,
+    * identifying it by the name of the tar file. If the $p_compress argument is
+    * set the tar will be read or created as a gzip or bz2 compressed TAR file.
+    *
+    * @param string $p_tarname
+    *   The name of the tar archive to create
+    * @param null|false|true|string $p_compress
+    *   Indicates whether compression is required. Must be one of the following:
+    *   - NULL: No compression is required.
+    *   - FALSE: No compression is required.
+    *   - TRUE: Gzip compression is required.
+    *   - '': No compression is required.
+    *   - 'gz': Gzip compression is required.
+    *   - 'bz2': Bzip2 compression is required.
     * @access public
     */
 //    function Archive_Tar($p_tarname, $p_compress = null)