After upgrade to Moodle 2.0.6, mod/url des not opens up anymore the original location. With debugging, the following message is displayed:

Warning: preg_replace_callback() [function.preg-replace-callback]: Compilation failed: range out of order in character class at offset 39 in /your/path/to/moodle/mod/url/locallib.php on line 95

To reproduce:

• on a 2.0.6 site, with Multimedia and Glossary filter on, turn debugging on
• add an URL resource pointing to an external link.
• configure the resource "view" option to "open" or "popup"
• click "save and view". The Warning in displayed, the url is not open in the popup, and the link is not printed when resource "view" option is set to "open"