Common subdirectories: /root/graphmath_captcha/fonts and /srv/www/drupal-7.14/sites/all/modules/captcha/graphmath_captcha/fonts
diff /root/graphmath_captcha/graphmath_captcha.module /srv/www/drupal-7.14/sites/all/modules/captcha/graphmath_captcha/graphmath_captcha.module
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< define('graphmath_captcha_ALLOWED_CHARACTERS', 'aAbBCdEeFfGHhijKLMmNPQRrSTtWXYZ23456789');
< 
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<  * Helper function for splitting an utf8 string correctly in characters.
<  * Assumes the given utf8 string is well formed.
<  * See http://en.wikipedia.org/wiki/Utf8 for more info
<  */
< function _graphmath_captcha_utf8_split($str) {
<   $characters = array();
<   $len = strlen($str);
<   for ($i=0; $i < $len; ) {
<     $chr = ord($str[$i]);
<     if (($chr & 0x80) == 0x00) { // one byte character (0zzzzzzz)
<       $width = 1;
<     }
<     else {
<       if (($chr & 0xE0) == 0xC0) { // two byte character (first byte: 110yyyyy)
<         $width = 2;
<       }
<       elseif (($chr & 0xF0) == 0xE0) { // three byte character (first byte: 1110xxxx)
<         $width = 3;
<       }
<       elseif (($chr & 0xF8) == 0xF0) { // four byte character (first byte: 11110www)
<         $width = 4;
<       }
<       else {
<         watchdog('CAPTCHA', 'Encountered an illegal byte while splitting an utf8 string in characters.', array(), WATCHDOG_ERROR);
<         return $characters;
<       }
<     }
<     $characters[] = substr($str, $i, $width);
<     $i += $width;
<   }
<   return $characters;
< }
< 
< /**
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>   $characters = array();
>   for ($i=0; $i<strlen($code); $i++) {
>     $characters[$i] = substr($code, $i, 1);
>   }
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<   $characters = _graphmath_captcha_utf8_split($code);
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< //        $allowed_chars = _graphmath_captcha_utf8_split(variable_get('graphmath_captcha_image_allowed_chars', graphmath_captcha_ALLOWED_CHARACTERS));
< //        $code_length = (int)variable_get('graphmath_captcha_code_length', 5);
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<         // TODO: start using a theming funtion for generating the image markup?
---
>         // TODO: start using a theming function for generating the image markup?
diff /root/graphmath_captcha/graphmath_captcha.user.inc /srv/www/drupal-7.14/sites/all/modules/captcha/graphmath_captcha/graphmath_captcha.user.inc
232c232,235
<   $characters = _graphmath_captcha_utf8_split($text);
---
>   $characters = array();
>   for ($i=0; $i<strlen($text); $i++) {
>     $characters[$i] = substr($text, $i, 1);
>   }