On the server (OpenSolaris 2009.06)…

time /usr/bin/grep XXX /tmp/xxx.txt > /dev/null

real    0m0.039s
user    0m0.031s
sys     0m0.008s

time /usr/gnu/bin/grep XXX /tmp/xxx.txt > /dev/null

real    1m22.448s
user    1m22.364s
sys     0m0.027s

And…

/usr/gnu/bin/grep –version
grep (GNU grep) 2.5

Copyright 1988, 1992-1999, 2000, 2001 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

So, on my desktop (Ubuntu 8.04)…

time /bin/grep XXX /tmp/xxx.txt > /dev/null
real    0m0.049s
user    0m0.044s
sys    0m0.004s

/bin/grep –version

GNU grep 2.5.3

Copyright (C) 1988, 1992-2002, 2004, 2005  Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

And on OpenSolaris the default grep is the gnu… WTF???