vtiger_users table is not created on Mysql version greater than 5.6.5

linked to http://code.vtiger.com/vtiger/vtigercrm/issues/202

mysql error on vtiger_users table creation

Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause

Changes in MySQL 5.6.5 (2012-04-10, Milestone 8)

Previously, at most one TIMESTAMP column per table could be automatically initialized or updated to the current date and time. This restriction has been lifted. Any TIMESTAMP column definition can have any combination of DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses. In addition, these clauses now can be used with DATETIME column definitions. For more information, see Automatic Initialization and Updating for TIMESTAMP and DATETIME.