--- src/mm/boehm-gc/configure.orig	2012-09-03 12:10:04.000000000 -0400
+++ src/mm/boehm-gc/configure	2012-09-19 14:42:52.000000000 -0400
@@ -5063,6 +5063,7 @@
 	$as_echo "#define GC_FREEBSD_THREADS 1" >>confdefs.h
 
 	INCLUDES="$INCLUDES -pthread"
+	THREADDLLIBS=-lpthread
       	;;
      *-*-kfreebsd*-gnu)
 	$as_echo "#define GC_FREEBSD_THREADS 1" >>confdefs.h
