Nope, I think it'd work for Lazarus, too, hence those two procedures are consisted in Windows API.
AddFontResource: http://msdn.microsoft.com/en-us/libr...8VS.85%29.aspx
RemoveFontResource: http://msdn.microsoft.com/en-us/libr...8VS.85%29.aspx

You might also consider using AddFontResourceEx and RemoveFontResourceEx. They allow to hide your font from other application, thus you don't have to use SendMessage to tell every other process there's a new font.