Using Group Policy in IE7 and Multiple Tabs

I've been asked to use a GPO to make our internal intranet everybody's home
page. That works just fine. However, doing so wipes out all additional home
page tabs that people have setup. Also, if I recreate all the extra home page
tabs and the GPO gets refreshed, those extra home page tabs get wiped out
again and the user is left with just the intranet as their solitary home page.

Is there a way to set a GPO so that all users get the intranet as their
"main" home page and can have all their other desired home pages as well?

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Tim