Regex does not match dailymotion URL

Hello,

Here is the URL i wanted to embed in my website :
http://www.dailymotion.com/video/xggkum_l-agriculture-familiale-peut-ell...

Here is the regex currently used by the module to get the id :
preg_match('/^https?:\/\/(www\.)?dailymotion.com\/video\/(?[a-z0-9]{7})(_([0-9a-zA-Z\-_])*)?$/', $input, $matches);

I found 2 distinct issues in the regex :
- The id does not contain 7 characters but only 6. I checked on many others dailymotion URL and the id was always composed of 6 characters, why does the regex provide 7 ?
- The regex does not allow specific characters such as '#' or '.' I think we can allow it at the end of the url because we only get the id from this regex and don't get the whole URL. Am I missing something ?