Erik Lindvall contributed a BSD/OS 4 patch for LDSHARED.
diff --git a/configure.in b/configure.in
index 5a46847..5932e06 100644
--- a/configure.in
+++ b/configure.in
@@ -467,6 +467,7 @@
 		fi ;;
 	Linux*) LDSHARED="gcc -shared";;
 	dgux*) LDSHARED="ld -G";;
+	BSD/OS*/4*) LDSHARED="gcc -shared";;
 	FreeBSD*/[[34]]*) LDSHARED="gcc -shared";;
 	FreeBSD*|OpenBSD*) LDSHARED="ld -Bshareable";;
 	NetBSD*)