How to press the AltGr key in a Wine app?

I'm playing a particular Windows game in Wine and it is looking for the Right Alt key to be pressed to do a particular function in the game. But when I press it, it doesn't do anything. I understand that the linux desktop has allocated, if that is the right word the AltGr key to do something else i.e. accents to different vowels, stuff like that. But is there a way to tell Wine that I want to press the AltGr as it was in Windows 98? Or even assign another key to that scancode? The game is from 2001 I think and I'm sure it is easy to do...if you know how. It's not terribly important but annoying not to know.