Ran into this (again, I think) today while setting up some assembly binding between Telerik and PeterBlum controls in my LakeQuincy web site. The short version is that the presence of an xmlns= in your <configuration> node of web.config will prevent ASP.NET 2.0 from reading any assemblyBinding tag. So if you have something like this:
Otherwise you may encounter something like this error:
Could not load file or assembly ‘RadComboBox.Net2, Version=2.0.3.0, Culture=neutral, PublicKeyToken=175e9829b585f1f6’ or one of its dependencies. The located assembly’s manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)