reg expression help

[eluser]amipaxs[/eluser]
Hello,

I can make this regular expression to replace any occurence of accented international characters ,

Code:

$string = preg_replace("[À|Á|Â|Ã|Ä|Å|à|á|â|ã|ä|å]","a",$str);

any help or tip is welcome
Rodrigo