I installed I libsem (
ftp://ftp.freeradius.org/ftp/radius/contrib/libsem.tar.gz ) and I occur the
following problem:

# ./configure
[snip]
checking for pthread.h... yes
checking for pthread_create in -lpthread... yes
checking for library containing sem_init... no
configure: error: -lsem not found.  You may want to download it from
ftp://ftp.to.gd-es.com/pub/BSDI/libsem.tar.bz2 or
ftp://ftp.freeradius.org/pub/radius/contrib/libsem.tar.gz
# ls /usr/lib/*sem*
/usr/lib/libsem.a
# 

-- 
Daniel Dias Gonçalves
f22@netbsd.com.br, f22@proveritauna.com.br