Description of problem: Regular expression in grep is misinterpreted/broken. It 
works on FreeBSD. It seems to effect all programs using regular expression.


Version-Release number of selected component (if applicable): grep-2.5.1-4


How reproducible:very


Steps to Reproduce: 
Using file: testgrep.txt
abcXYZ
abcd
XYZ

1. 
Actual results:

grep [A-Z] testgrep.txt   - DOES NOT WORK! Lower case "abcd" should not printed.
abcXYZ
abcd
XYZ

grep [YZ] testgrep.txt        - WORKS!
abcXYZ
XYZ

grep [a-z] testgrep.txt       - DOES NOT WORK! Should not print XYZ
abcXYZ
abcd
XYZ

grep [Y-Z] testgrep.txt       - WORKS!
abcXYZ
XYZ


Expected results: As described above. It works properly on FreeBSD.

Additional info: Probably a broken regex C library routine. As this is a basic 
routine used in so many commands and applications, it is A VERY SERIOUS ERROR.