Hi,
Try to change $mysqldb parameter in webim/libs/config.php to
the name that deffers from 'webim' (for example it can be called 'another_webim')
and install mibew, by typing
http://yourhost/webim/install/ in a browser address line.
If your mysql user have permission to creating databases, the 'another_webim'
database would created automatically.
But if your mysql user have no such permissions you must manually create this
database, next specify in $mysqldb the name of the created database and after all install mibew.
Hope it helps,
Dmitriy.