diff --git a/libraries/libldap_r/Makefile.in b/libraries/libldap_r/Makefile.in
index 48df9f7550..5316822393 100644
--- a/libraries/libldap_r/Makefile.in
+++ b/libraries/libldap_r/Makefile.in
@@ -56,7 +56,7 @@ XLIBS = $(LIBRARY) $(LDAP_LIBLBER_LA) $(LDAP_LIBLUTIL_A)
 XXLIBS = $(SECURITY_LIBS) $(LUTIL_LIBS)
 XXXLIBS = $(LTHREAD_LIBS)
 NT_LINK_LIBS = $(LDAP_LIBLBER_LA) $(AC_LIBS) $(SECURITY_LIBS)
-UNIX_LINK_LIBS = $(LDAP_LIBLBER_LA) $(AC_LIBS) $(SECURITY_LIBS)
+UNIX_LINK_LIBS = $(LDAP_LIBLBER_LA) $(AC_LIBS) $(SECURITY_LIBS) $(LTHREAD_LIBS)
 
 .links : Makefile
 	@for i in $(XXSRCS); do \