If you create portal listings regularly within your SharePoint portal, you may have noticed that sometimes you see the Start Date and Expiration Date fields, and other times you don't.
Well, it turns out that SharePoint uses a different template for the Add Listing page depending on whether the area uses the News Area Template or not.
The good news is that you can change the template used by altering the URL for the Add Listing page. Just append "&Mode=News" to the end of the URL to see the date fields.
For example, if your "Add Listing" URL looks like this:
http://Portal/_layouts/1033/spnewlisting.aspx?CatID=3b6a1210-54fb-4ed8-811f-b3d0cd415d2
Simply change it to this to see the date fields:
http://Portal/_layouts/1033/spnewlisting.aspx?CatID=3b6a1210-54fb-4ed8-811f-b3d0cd415d2&Mode=New