Regular expression mystery.

[David Harel]

In the commands below I insert data to grep via standard input and 
terminate with <Ctrl-D>. Lines that match the expression are echoed 
back. To improve visibility I used -n option so we can see the line 
number of the matched line. BUT.
Can anyone explain the following behavior?
Did anyone fiddle with the weight of letters?

Right
==========================================================
[EMAIL PROTECTED] tmp]$ grep -n '[ABCDEFGHIJKLMNOPQRSTUVWXYZ]'
123
abc
ABC
3:ABC
Wrong
====================================
[EMAIL PROTECTED] tmp]$ grep -n '[A-Z]'
123
ABC
2:ABC
abc
3:abc
--
Thanks.
David Harel,
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