Index: wp-includes/formatting.php
===================================================================
--- wp-includes/formatting.php	(revision 17198)
+++ wp-includes/formatting.php	(working copy)
@@ -73,7 +73,7 @@
 	for ( $i = 0; $i < $stop; $i++ ) {
 		$curl = $textarr[$i];
 
-		if ( !empty($curl) && '<' != $curl[0] && '[' != $curl[0]
+		if ( !empty($curl) && '<' != $curl[0] && '[' != $curl[0] && trim($curl) != '-->'
 				&& empty($no_texturize_shortcodes_stack) && empty($no_texturize_tags_stack)) {
 			// This is not a tag, nor is the texturization disabled
 			// static strings