I'm able to replace it with something else but this is not the result i want.

Ex; the user John D'amour  with my current naming format will have for logon name d'amojo

But it must be damoujo or damojo

I tried to trick the  umlaut table but i can only replace it and not remove it completely.

I already tried replacing with a space as the spaces are trimmed, invalid character like \ etc.. and nothing works.

Any suggestion are welcome.