Index: wp-admin/users.php
===================================================================
--- wp-admin/users.php	(revision 19633)
+++ wp-admin/users.php	(working copy)
@@ -382,6 +382,8 @@
 	</div>
 <?php endif;
 
+$messages = apply_filters( 'admin_messages', $messages );
+
 if ( ! empty($messages) ) {
 	foreach ( $messages as $msg )
 		echo $msg;
Index: wp-admin/edit-comments.php
===================================================================
--- wp-admin/edit-comments.php	(revision 19633)
+++ wp-admin/edit-comments.php	(working copy)
@@ -220,6 +220,8 @@
 			}
 		}
 
+		$messages = apply_filters( 'admin_messages', $messages );
+
 		echo '<div id="moderated" class="updated"><p>' . implode( "<br/>\n", $messages ) . '</p></div>';
 	}
 }
Index: wp-admin/edit-tags.php
===================================================================
--- wp-admin/edit-tags.php	(revision 19633)
+++ wp-admin/edit-tags.php	(working copy)
@@ -269,7 +269,8 @@
 </h2>
 
 <?php if ( isset($_REQUEST['message']) && ( $msg = (int) $_REQUEST['message'] ) ) : ?>
-<div id="message" class="updated"><p><?php echo $messages[$msg]; ?></p></div>
+<?php $message = apply_filters( 'admin_message', $messages[$msg], $messages, $_REQUEST['message'] ); ?>
+<div id="message" class="updated"><p><?php echo $message; ?></p></div>
 <?php $_SERVER['REQUEST_URI'] = remove_query_arg(array('message'), $_SERVER['REQUEST_URI']);
 endif; ?>
 <div id="ajax-response"></div>
Index: wp-admin/user-new.php
===================================================================
--- wp-admin/user-new.php	(revision 19633)
+++ wp-admin/user-new.php	(working copy)
@@ -231,6 +231,8 @@
 	</div>
 <?php endif;
 
+$messages = apply_filters( 'admin_messages', $messages );
+
 if ( ! empty( $messages ) ) {
 	foreach ( $messages as $msg )
 		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
Index: wp-admin/upload.php
===================================================================
--- wp-admin/upload.php	(revision 19633)
+++ wp-admin/upload.php	(working copy)
@@ -220,6 +220,8 @@
 	$_SERVER['REQUEST_URI'] = remove_query_arg(array('message'), $_SERVER['REQUEST_URI']);
 }
 
+$message = apply_filters( 'admin_message', $message, $messages, $_GET['message'] );
+
 if ( !empty($message) ) { ?>
 <div id="message" class="updated"><p><?php echo $message; ?></p></div>
 <?php } ?>
Index: wp-admin/network/site-new.php
===================================================================
--- wp-admin/network/site-new.php	(revision 19633)
+++ wp-admin/network/site-new.php	(working copy)
@@ -112,6 +112,7 @@
 <?php screen_icon('ms-admin'); ?>
 <h2 id="add-new-site"><?php _e('Add New Site') ?></h2>
 <?php
+$messages = apply_filters( 'admin_messages', $messages );
 if ( ! empty( $messages ) ) {
 	foreach ( $messages as $msg )
 		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
Index: wp-admin/network/site-info.php
===================================================================
--- wp-admin/network/site-info.php	(revision 19633)
+++ wp-admin/network/site-info.php	(working copy)
@@ -113,6 +113,7 @@
 ?>
 </h3>
 <?php
+$messages = apply_filters( 'admin_messages', $messages );
 if ( ! empty( $messages ) ) {
 	foreach ( $messages as $msg )
 		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
Index: wp-admin/network/site-settings.php
===================================================================
--- wp-admin/network/site-settings.php	(revision 19633)
+++ wp-admin/network/site-settings.php	(working copy)
@@ -104,6 +104,7 @@
 </h3>
 <?php
 if ( ! empty( $messages ) ) {
+	$messages = apply_filters( 'admin_messages', $messages );
 	foreach ( $messages as $msg )
 		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
 } ?>
Index: wp-admin/network/user-new.php
===================================================================
--- wp-admin/network/user-new.php	(revision 19633)
+++ wp-admin/network/user-new.php	(working copy)
@@ -74,6 +74,7 @@
 <h2 id="add-new-user"><?php _e('Add New User') ?></h2>
 <?php
 if ( ! empty( $messages ) ) {
+	$messages = apply_filters( 'admin_messages', $messages );
 	foreach ( $messages as $msg )
 		echo '<div id="message" class="updated"><p>' . $msg . '</p></div>';
 }
Index: wp-admin/nav-menus.php
===================================================================
--- wp-admin/nav-menus.php	(revision 19633)
+++ wp-admin/nav-menus.php	(working copy)
@@ -473,6 +473,9 @@
 	<?php screen_icon(); ?>
 	<h2><?php esc_html_e('Menus'); ?></h2>
 	<?php
+
+	$messages = apply_filters( 'admin_messages', $messages );
+
 	foreach( $messages as $message ) :
 		echo $message . "\n";
 	endforeach;
Index: wp-admin/edit.php
===================================================================
--- wp-admin/edit.php	(revision 19633)
+++ wp-admin/edit.php	(working copy)
@@ -260,6 +260,8 @@
 	unset($_REQUEST['undeleted']);
 }
 
+$messages = apply_filters( 'admin_messages', $messages );
+
 if ( $messages )
 	echo join( ' ', $messages );
 unset( $messages );
Index: wp-admin/widgets.php
===================================================================
--- wp-admin/widgets.php	(revision 19633)
+++ wp-admin/widgets.php	(working copy)
@@ -319,7 +319,8 @@
 <h2><?php echo esc_html( $title ); ?></h2>
 
 <?php if ( isset($_GET['message']) && isset($messages[$_GET['message']]) ) { ?>
-<div id="message" class="updated"><p><?php echo $messages[$_GET['message']]; ?></p></div>
+<?php	$message = apply_filters( 'admin_message', $messages[$_GET['message']], $messages, $_GET['message'] ); ?>
+<div id="message" class="updated"><p><?php echo $message; ?></p></div>
 <?php } ?>
 <?php if ( isset($_GET['error']) && isset($errors[$_GET['error']]) ) { ?>
 <div id="message" class="error"><p><?php echo $errors[$_GET['error']]; ?></p></div>