The upload of a zipped file doesn't work in the document tool, why?
From ClarolineDoc
You need to activate Zlib library (http://www.php.net/zlib) in the file php.ini
If Zlib library is activated, verify the limits for the following settings in php.ini :
- upload_max_filesize
- post_max_size
- max_execution_time
- LimitRequestBody

