diff --git a/PHP Markdown Readme.text b/PHP Markdown Readme.text
index 840076c..ab4ce60 100644
--- a/PHP Markdown Readme.text	
+++ b/PHP Markdown Readme.text	
@@ -209,6 +209,10 @@ Version History
 	`pre` tags at the end of a code block were appearing in the wrong 
 	order.
 
+*	Overriding configuration settings by defining constants from an 
+	external before markdown.php is included is now possible without 
+	producing a PHP warning.
+
 
 1.0.1i (31 Aug 2007):
 
diff --git a/markdown.php b/markdown.php
index 3fc674d..5551923 100644
--- a/markdown.php
+++ b/markdown.php
@@ -20,10 +20,10 @@ define( 'MARKDOWN_VERSION',  "1.0.1j" ); # Tue 4 Sep 2007
 #
 
 # Change to ">" for HTML output
-define( 'MARKDOWN_EMPTY_ELEMENT_SUFFIX',  " />");
+@define( 'MARKDOWN_EMPTY_ELEMENT_SUFFIX',  " />");
 
 # Define the width of a tab for code blocks.
-define( 'MARKDOWN_TAB_WIDTH',     4 );
+@define( 'MARKDOWN_TAB_WIDTH',     4 );
 
 
 #
@@ -31,14 +31,14 @@ define( 'MARKDOWN_TAB_WIDTH',     4 );
 #
 
 # Change to false to remove Markdown from posts and/or comments.
-define( 'MARKDOWN_WP_POSTS',      true );
-define( 'MARKDOWN_WP_COMMENTS',   true );
+@define( 'MARKDOWN_WP_POSTS',      true );
+@define( 'MARKDOWN_WP_COMMENTS',   true );
 
 
 
 ### Standard Function Interface ###
 
-define( 'MARKDOWN_PARSER_CLASS',  'Markdown_Parser' );
+@define( 'MARKDOWN_PARSER_CLASS',  'Markdown_Parser' );
 
 function Markdown($text) {
 #