Reference to a non-shared member requires an object reference

I do not receive this error when I open my website application in vs 2005. When I open in vs 2008, I get this error. What gives?
These lines are underlined in blue:
<%Dim cust As New BusinessLogic.SiteUser(CInt(BusinessLogic.SiteUser.CurrUserID))%>
Businesslogic area is imported into each of 3 pages with this line. 
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