diff --git a/wp-includes/js/tinymce/plugins/wordpress/editor_plugin_src.js b/wp-includes/js/tinymce/plugins/wordpress/editor_plugin_src.js
index 2c11519631..0e7a93731e 100644
--- a/wp-includes/js/tinymce/plugins/wordpress/editor_plugin_src.js
+++ b/wp-includes/js/tinymce/plugins/wordpress/editor_plugin_src.js
@@ -249,10 +249,10 @@
 			t._handleMoreBreak(ed, url);
 
 			// Add custom shortcuts
-			mod_key = 'alt';
+			mod_key = 'alt+shift';
 
-			if ( tinymce.isIE || tinymce.isOpera )
-				mod_key = 'shift+alt';
+			if ( tinymce.isGecko )
+				mod_key = 'ctrl+alt';
 
 			ed.addShortcut(mod_key + '+c', 'justifycenter_desc', 'JustifyCenter');
 			ed.addShortcut(mod_key + '+r', 'justifyright_desc', 'JustifyRight');
diff --git a/wp-includes/js/tinymce/wp-mce-help.php b/wp-includes/js/tinymce/wp-mce-help.php
index add970e77b..3e04a97c10 100644
--- a/wp-includes/js/tinymce/wp-mce-help.php
+++ b/wp-includes/js/tinymce/wp-mce-help.php
@@ -204,7 +204,7 @@ if ( tinymce.isMac )
 		<tr><th>6</th><td><?php _e('Heading 6') ?></td><th>9</th><td><?php _e('Address') ?></td></tr>
 	</table>
 
-	<p><?php _e('The following shortcuts use different access keys: Alt + letter in Firefox, Chrome and Safari, Alt + Shift + letter in Internet Explorer and Opera.') ?></p>
+	<p><?php _e('The following shortcuts use different access keys: Alt + Shift + letter in Chrome, Safari, Internet Explorer and Opera, and Ctrl + Alt + letter (Command + Option + letter on Macintosh) in Firefox.') ?></p>
 	<table class="keys">
 		<tr class="top"><th class="key center"><?php _e('Letter') ?></th><th class="left"><?php _e('Action') ?></th><th class="key center"><?php _e('Letter') ?></th><th class="left"><?php _e('Action') ?></th></tr>
 		<tr><th>n</th><td><?php _e('Check Spelling') ?></td><th>l</th><td><?php _e('Align Left') ?></td></tr>