Creating tasks on mass update of contact record

Does userevent type serversuitescript trigger on mass update??
I am trying to create tasks on already existing contact records. I have created a server suitescript that creates a task for the contact when it is updated indivisualy/manualy but when i try to do mass update using the mass update assistant it doesnot create tasks for the contacts.
I am wondering if that is the expected behaviour or should the userevent script trigger on the mass update?

Please guide me as to how to achieve creating tasks on mass update of contacts.

Thanks,