如何在错误日志（Joomla K2）中修复此错误？
href='function.preg-match'>function.preg-match</a>]: Compilation failed: invalid range in character class at offset 7 in /home/tesstr13/public_html/administrator/components/com_k2/lib/class.upload.php on line 2843
[12-Apr-2014 21:03:21 Europe/Amsterdam] PHP Warning: preg_match() [<a href='function.preg-match'>function.preg-match</a>]: Compilation failed: invalid range in character class at offset 7 in /home/tesstr13/public_html/administrator/components/com_k2/lib/class.upload.php on line 2870
[12-Apr-2014 21:03:21 Europe/Amsterdam] PHP Warning: preg_match() [<a href='function.preg-match'>function.preg-match</a>]: Compilation failed: invalid range in character class at offset 7 in /home/tesstr13/public_html/administrator/components/com_k2/lib/class.upload.php on line 2915
这样的错误数以千计。