FYI , the latest Q2A 1.7 Beta , you wont get this error anymore .
If you are still using the q2a 1.6 then use the below method You dont have to edit the php.ini file .
1. Openup the qa-include/qa-db.php
2. add the below line after the liscence comment (before the actual functions starts )
error_reporting(E_ALL ^ E_DEPRECATED);
3. This should solve your issue .