Is there a way to modify the caption of messagebox() command buttons?

For example, suppose I wanted the command buttons of a "Yes, No, Cancel" to read "Up, Down, Sideways" ... ?

Ssince all messagebox does is return 6=Yes, 7=No, or 2=Cancel, it would be a no brainer to interpret return codes and do whatever. With all the flexibility available, but it seems "peculiar" that there isn't a backdoor for get at properties of those controls.

Is my only option to create my own class?