+ // Normalize Halfwidth and Fullwidth Unicode block that IE6 might treat as ascii
+ $value = preg_replace_callback(
+ '/[!-z]/u', // U+FF01 to U+FF5A
+ function ( $matches ) {
+ $cp = utf8ToCodepoint( $matches[0] );
+ if ( $cp === false ) {
+ return '';
+ }
+ return chr( $cp - 65248 ); // ASCII range \x21-\x7A
+ },
+ $value
+ );
+
+ // Convert more characters IE6 might treat as ascii
+ // U+0280, U+0274, U+207F, U+029F, U+026A, U+207D, U+208D
+ $value = str_replace(
+ array( 'ʀ', 'ɴ', 'ⁿ', 'ʟ', 'ɪ', '⁽', '₍' ),
+ array( 'r', 'n', 'n', 'l', 'i', '(', '(' ),
+ $value
+ );
+