Timing out in Blackboard with IE 7

I'm an on-line college instructor using Blackboard 7.0, and immediately after installing IE 7.0 (2 weeks ago) I started having a problem with getting timed out any time I take more than 5 minutes to grade student papers. I've worked with our system Blackboard people, and no one else can replicate this with any other browser.

I open a page with forms for entering comments and student grades, click a link to open the student submitted paper, read it, compose comments in the form and click to submit. If I can finish this task within 5 minutes (any one who grades essays knows this is not likely), everything proceeds normally. If I go over 5 minutes, when I click to submit, I get a Blackboard error message saying that I am no longer logged in (that I have timed out), and must complete a lengthy process to log in again, find the gradebook, find the student, open the item to be graded, and this time type in the comments and grade within 5 minutes.

Anyone heard of time-out experiences in any similar situations?

[1041 byte] By [lillirose] at [2007-12-27]