diff --git a/libraries/libldap/tls2.c b/libraries/libldap/tls2.c
index d25c190..94399d7 100644
--- a/libraries/libldap/tls2.c
+++ b/libraries/libldap/tls2.c
@@ -149,6 +149,9 @@ ldap_pvt_tls_destroy( void )
 	tls_imp->ti_tls_destroy();
 }
 
+#ifdef LDAP_R_COMPILE
+static pthread_once_t tlsm_initialized = PTHREAD_ONCE_INIT;
+#endif
 /*
  * Initialize a particular TLS implementation.
  * Called once per implementation.
@@ -158,6 +161,10 @@ tls_init(tls_impl *impl )
 {
 	static int tls_initialized = 0;
 
+#ifdef LDAP_R_COMPILE
+	(void)pthread_once(&tlsm_initialized, impl->ti_thr_init);
+#endif
+
 	if ( !tls_initialized++ ) {
 #ifdef LDAP_R_COMPILE
 		ldap_pvt_thread_mutex_init( &tls_def_ctx_mutex );
@@ -166,9 +173,6 @@ tls_init(tls_impl *impl )
 
 	if ( impl->ti_inited++ ) return 0;
 
-#ifdef LDAP_R_COMPILE
-	impl->ti_thr_init();
-#endif
 	return impl->ti_tls_init();
 }