This really stumped me and I have to admit I had given up trying to work this one out! However, whilst trawling through the ref I accidentally stumbled on this class. I know it isn't exactly what you were after since you would need to do it as a Plugin as oppose to doing it via the framework but atleast it's half way and might be of some use possibly....
System.Windows.Forms.TextBoxBase myControl = new System.Windows.Forms.TextBoxBase();