Sort exists, and in path, but global cannot find it

[Suresh Govindachar]

Hello,

I have sort, as follows:

   $ which sort
   /bin/sort
   $ sort --version
   sort (GNU coreutils) 5.97
   Copyright (C) 2006 Free Software Foundation, Inc.
   This is free software.  You may redistribute copies of it under the terms of
   the GNU General Public License <http://www.gnu.org/licenses/gpl.html>.
   There is NO WARRANTY, to the extent permitted by law.
   
   Written by Mike Haertel and Paul Eggert.

However, sometimes global will warn:

  Warning: POSIX sort program not found. If available, the program will be 
speed up.

What needs to be done to satisfy the warning message?

Thanks,

--Suresh