Index: wp-admin/includes/screen.php
===================================================================
--- wp-admin/includes/screen.php	(revision 18925)
+++ wp-admin/includes/screen.php	(working copy)
@@ -590,7 +590,7 @@
 	 *
 	 * @param array $args
 	 * - string   - title    - Title for the tab.
-	 * - string   - id       - Tab ID. Optional.
+	 * - string   - id       - Tab ID. Must be HTML-safe.
 	 * - string   - content  - Help tab content in plain text or HTML. Optional.
 	 * - callback - callback - A callback to generate the tab content. Optional.
 	 *
@@ -608,9 +608,9 @@
 		if ( ! $args['title'] )
 			return;
 
-		// Create an id from the title if one is not provided.
+		// Ensure we have an id.
 		if ( ! $args['id'] )
-			$args['id'] = sanitize_html_class( $args['title'] );
+			return;
 
 		$this->_help_tabs[] = $args;
 	}