Two Types not equal that should be

I'm trying to debug some code that uses reflection to load plugins

Here's the debugging code:

Type a = methodInfo.GetParameters()[0]
    .ParameterType.BaseType;
Type b = typeof(MessageContext);
Debug.WriteLine(a.AssemblyQualifiedName);
Debug.WriteLine(b.AssemblyQualifiedName);
Debug.WriteLine(a.Equals(b));

And here is its output:

OrtzIRC.Common.MessageContext, OrtzIRC.Common, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
OrtzIRC.Common.MessageContext, OrtzIRC.Common, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
False

I don't understand what would make these two types different?