[Debian] grep поломался :(

$ echo aaaaaaaaay | LANG=C grep -E '[A-Z]'
$

... For example, in the default C locale, [a-d] is equivalent  to  [abcd].
       Many  locales  sort  characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd],
       for example.  To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable  to  the
       value C ...