Accented characters not recognized when LANG=en_US.UTF-8

Hi everybody,

In RH9, I'm having the following problem when usings XEmacs:

when I type accented characters, like (dead-grave a), xemacs complains 
"U00E0 not defined". 

This only happens when LANG=en_US.UTF-8, which was set as default in my installation of RH9. When I set LANG=en_US before invoking xemacs, accented characters are printed ok. I wonder if the UTF-8 input is broken. Displaying utf-8 encoded files works fine, the problem is only when I type the accented characters.

On other applications, like gnome-console and VIM, entering accented characters works fine when LANG=en_US.UTF-8, but fails for LANG=en_US. 

I wonder if someone knows an easy way to fix this.

Thanks,
Fabricio