Revolution: Removing unwanted forreign characters on file upload that breaks stuff like phpthumb

<?php
/**
 * MODx SanitiX sanitize filename plugin for the file manager upload process
 *
 * @author exside
 * @credits:
 * 		- Based on the code of the sanitizefilename plugin of Benjamin Vauchel https://github.com/benjamin-vauchel/SanitizeFilename
 * 		- The Slug() phunction of AlixAxel https://github.com/alixaxel/phunction/blob/master/phunction/Text.php
 * @version Version 1.1
 * @modified 26.11.2012
 *
 * @description 
 * Remove unwanted characters from uploaded filenames and replace accented-characters with "normal" ones based on transliteration & language
 * Example : a file with the following name "gäñz leidä file#nàmä mît jéglèçhem shì@t w0mä n!d sött.png" 
 * will be "gaenz_leidae_file_namae_mit_jeglechem_shi_t_w0mae_n_d_soett.png" (in a german environment with culturKey 'de')
 *
 * If a file already exists (with the sanitized filename), _duplicate is attached to the filename
 *
 * You can change the character that is used to replace spaces and special chars by specifing it in the $slug variable below, defaults to _
 *
 * Events: OnFileManagerUpload
 *
 * @package SanitiX
 */

// Cleaning function
if ( !function_exists('cleanFilename')) {
	function cleanFilename($modx, $filename, $slug) {

		// trim, lowercase, replace special chars, transliterate
		if (function_exists('iconv')) {
			// iconv somehow doesn't work without this and it doesn't sem to be set by modx
			setlocale(LC_ALL, strtolower($modx->getOption('cultureKey')) . '_' . strtoupper($modx->getOption('cultureKey')));
			
			$filename = strtolower(trim(preg_replace('~[^0-9a-z' . preg_quote(null, '~') . ']+~i', $slug, iconv('UTF-8', 'ASCII//TRANSLIT', $filename)), $slug));
			
			//$modx->log(modX::LOG_LEVEL_ERROR, '[SanitiX] transliteraded filename: ' . $filename);
		} else {
			$modx->log(modX::LOG_LEVEL_ERROR, '[SanitiX] No iconv functions available, cannot transliterate the filename, that\'s why it looks ugly');

			$filename = strtolower(trim(preg_replace('~[^0-9a-z' . preg_quote(null, '~') . ']+~i', $slug, $filename), $slug));
		}

		if ( empty($filename) ) {
			return 'noname';
		}

		return $filename;
	}
}

// We rename each of the uploaded files
foreach( $files as $file ) {
	if ( $file['error'] == 0 ) {
		$slug = '_';
		$pathInfo = pathinfo($file['name']);
		$basePath = $source->getBasePath();

		$oldPath = $directory . $file['name'];
		
		$newPath = cleanFilename($modx, $pathInfo['filename'], $slug) . '.' . $pathInfo['extension'];
		
		if ( file_exists($basePath . $directory . $newPath) ) {
			$newPath = cleanFilename($modx, $pathInfo['filename'], $slug) . '_duplicate.' . $pathInfo['extension'];
		}

		$source->renameObject($oldPath, $newPath);
	} else {
		$modx->log(modX::LOG_LEVEL_ERROR, '[SanitiX] There was an error during the upload process...');
	}
}

 if ( file_exists($basePath . $newPath) ) { ...