trying to compile OO2-devel on RELENG_6

[Bartosz Fabianowski]

> /usr/lib/libpthread.so: undefined reference to `__usleep'

See this message:
http://lists.freebsd.org/pipermail/freebsd-ia64/2005-October/000979.html

Quote:
I'm not aware of libpthread being broken that way. My guess is that
something in the build environment is broken. Given the difference
between 6.x and 7.x, I suspect you have a 7.x libpthread in a 6.x
environment (that is, a 6.x libc). Only libc in 7.x defines __usleep().

So, it seems that something is wrong with your pthread library / libc 
combination and thus, with your base system.

- Bartosz