diff -Naur -x unp*.h -x *.lh -x configure unpv12e.orig/server/lock_pthread.c unpv12e/server/lock_pthread.c
--- unpv12e.orig/server/lock_pthread.c	Sat Nov 16 10:51:56 1996
+++ unpv12e/server/lock_pthread.c	Fri Aug 17 17:08:41 2001
@@ -17,7 +17,13 @@
 	Close(fd);
 
 	Pthread_mutexattr_init(&mattr);
+
+#ifdef	_POSIX_THREAD_PROCESS_SHARED
 	Pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED);
+#else
+	errno = ENOSYS;
+	err_sys("my_lock_init: pthread_mutexattr_setpshared not supported on this system");
+#endif
 	Pthread_mutex_init(mptr, &mattr);
 }
 /* end my_lock_init */