Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 22133)
+++ wp-includes/functions.php	(working copy)
@@ -251,7 +251,7 @@
 	$data = trim( $data );
  	if ( 'N;' == $data )
 		return true;
-	$length = strlen( $data );
+	$length = count( str_split( $data ) );
 	if ( $length < 4 )
 		return false;
 	if ( ':' !== $data[1] )
@@ -288,7 +288,7 @@
 	if ( !is_string( $data ) )
 		return false;
 	$data = trim( $data );
-	$length = strlen( $data );
+	$length = count( str_split( $data ) );
 	if ( $length < 4 )
 		return false;
 	elseif ( ':' !== $data[1] )