I also booted the Xubuntu 11.10 i386 live cd on another computer, and found the same problem in xfce4-terminal, after installing xfce4-xkb-plugin and the Maori layout. However the AltGr + vowel combinations worked in Pidgin, which I tried.
So this problem is not confined to the 64-bit version.
I also booted the Xubuntu 11.10 i386 live cd on another computer, and found the same problem in xfce4-terminal, after installing xfce4-xkb-plugin and the Maori layout. However the AltGr + vowel combinations worked in Pidgin, which I tried.
So this problem is not confined to the 64-bit version.