Thread Safety problem on Solaris 10

Hi,

I'm tring to compile PG 8.1.2 with the option --enable-thread-safety on
Solaris 10 (with AMD64 opteron).

The gmake fails, ending with this output :

gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Winline
-Wdeclaration-after-statement -Wendif-labels -fno-strict-aliasing initdb.o
-L../../../src/port -lpgport -L../../../src/interfaces/libpq -lpq
-L../../../src/port -L/opt/sfw/lib -Wl,-rpath,/usr/local/pgsql/lib -lpgport
-lz -lreadline -ltermcap -lrt -lresolv -lgen -lsocket -lnsl -ldl -lm -o
initdb
../../../src/interfaces/libpq/libpq.so: undefined reference to
`write(at)SUNW_0(dot)9'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`fcntl(at)SUNW_0(dot)9'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`pthread_sigmask(at)SUNW_0(dot)9'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`close(at)SUNW_0(dot)9'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`read(at)SUNW_0(dot)9'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`poll(at)SUNW_1(dot)2'
../../../src/interfaces/libpq/libpq.so: undefined reference to
`sigaction(at)SUNW_0(dot)9'
collect2: ld returned 1 exit status
gmake[3]: *** [initdb] Error 1
gmake[3]: Leaving directory `/export/home0/postgres/pg_install/postgresql-
8.1.2/src/bin/initdb'
gmake[2]: *** [all] Error 2
gmake[2]: Leaving directory `/export/home0/postgres/pg_install/postgresql-
8.1.2/src/bin'
gmake[1]: *** [all] Error 2
gmake[1]: Leaving directory `/export/home0/postgres/pg_install/postgresql-
8.1.2/src'
gmake: *** [all] Error 2

Help would be appreciated.

Thanks,
Paul