Reflector 7.0.0.272. I'll describe what I'm seeing in my environment, though I'm sure you can recreate the issue using other specific assemblies.
- Open Reflector on a Windows Server 2008 with Windows Identity Foundation, .NET 3.5, and .NET 4.0 installed. The important part here is that WIF is bound to .NET 3.5 (mscorlib 2.0.0.0).
- Create a new list with .NET 4.0 assemblies.
- Open the GAC and add Microsoft.IdentityModel to the list of assemblies (that's from WIF).
- Do File -> Reorder Assemblies.
- The reordered list has BOTH mscorlib 4.0.0.0 (which was there from the original list you created) AND mscorlib 2.0.0.0 (mysteriously added during the reorder).
I don't expect the contents of the list to change during reorder.
- Open Reflector on a Windows Server 2008 with Windows Identity Foundation, .NET 3.5, and .NET 4.0 installed. The important part here is that WIF is bound to .NET 3.5 (mscorlib 2.0.0.0).
- Create a new list with .NET 4.0 assemblies.
- Open the GAC and add Microsoft.IdentityModel to the list of assemblies (that's from WIF).
- Do File -> Reorder Assemblies.
- The reordered list has BOTH mscorlib 4.0.0.0 (which was there from the original list you created) AND mscorlib 2.0.0.0 (mysteriously added during the reorder).
I don't expect the contents of the list to change during reorder.