VS2008 keeps adding 8.1 reference

I recently upgradded from NetAdvantage 8.1 to 8.3.  I upgraded my VB.NET 3.5 project in VS2008 to use 8.3 and everything works fine.  However, if I add an Ultra control from the toolbox onto my form, VS2008 adds an 8.1 reference, which ends up resulting in an ambiguous reference since both 8.1 and 8.3 references are present.  I have to manually delete the 8.1 references over and over again.