Difining time of logon

I have noticed that the time of logon in my restricted pages is very short. This user does not have time to carry through current tasks in the page as to fill out a long form. I would like to know how can I define the time of logon of the page using Dreamweaver MX (or its extensions). If it is not possible in Dreamweaver MX what code would I need for this task? Thanks!