See vidhi1987,
According to their website the deadline was July 15, 2012 for Winter Intake.
http://gradstudies.uoit.ca/future_students/application_process_and_requirement/step%202/index.php
But one can also submit the application, once the deadline has passed. But it will be considered only when there will be any space.
Here is the Quote from their website :
Priority will be given to applications that are received by the application deadline for the program. Applications after that date will be considered on a case-by-case basis provided there is still space available. Applicants should contact the graduate program director to inquire whether there is still space in the program. Late applications are received online under the next available admission deadline and will be considered as late applications for the earlier deadline should they be identified as such by the graduate program director.
So, just email them and ask.
One more thing that their OGS (Office of Graduate Studies) building is shifting to a new place, so because of this there must be some delay in their reply.
Do mail them once more, they will surely respond.
Cheers
Abhi