Unable to cast object of type System.RuntimeType to System.Enum

I've been tasked to generate a dynamic enumeration that has database driven values to alleviate recompiling and deployment of the Enum object when new values are added. The enumeration will exist as part of a internally consumed service.

The natural and most obvious advantage of this approach I suppose would be that anyone having need to consume the service would know immediately what values are available during development.

I'm not a big fan of this approach but I am up for the challenge.

The following code produces a RuntimeType but it throws an error on every attempt I've made in effort to cast this as an Enum.

    public Enum GenerateDynamicSmsEnumValues<T>(Dictionary<int,string> enumValues)
    {
        try
        {
            //    Create Base Assembly Objects
            AppDomain appDomain = AppDomain.CurrentDomain;
            AssemblyName asmName = new AssemblyName("SmsApplicationID");
            AssemblyBuilder asmBuilder = appDomain.
              DefineDynamicAssembly(asmName, AssemblyBuilderAccess.Run);

            //    Create Module and Enumeration Builder Objects
            ModuleBuilder modBuilder = asmBuilder.
              DefineDynamicModule("SmsApplicationID");
            EnumBuilder enumBuilder = modBuilder.
              DefineEnum("SmsApplicationID", TypeAttributes.Public, typeof(int));

            //  Build enumerations
            foreach (var pair in enumValues)
                enumBuilder.DefineLiteral(pair.Value, pair.Key);

            var returnType = enumBuilder.CreateType();
            var enm = (object)returnType;

            return (Enum)enm; // <-- Error Thrown Here
        }
        catch(Exception ex)
        {
            return null;
        }

If I inspect the object before the attempted cast the IsEnum attribute is set to true so I believe I have the object I need.

I just cannot figure out how to properly cast it to an Enum type to be used by any code leveraging the method.

I have also tried this approach using a Generic Template method but the problem is pretty much the same.

How can I cast this to an Enum object???