Does our kernel actually support this flag? Looking at the linux compat layer code, this flag is currently ignored.
You are right, it became available with FreeBSD 6.0.
If it is really the case, it should be better to remove it from the .h file, as some configure scripts try to detect if they could use this flag or not.
I added it to be able to build glibc-2.4 snapshot. Petr