diff --git a/conf/options/charon.opt b/conf/options/charon.opt
index 816f3250c..a4e03d4af 100644
--- a/conf/options/charon.opt
+++ b/conf/options/charon.opt
@@ -283,7 +283,7 @@ charon.retry_initiate_interval = 0
 	resolution failed), 0 to disable retries.
 
 charon.reuse_ikesa = yes
-	Initiate CHILD_SA within existing IKE_SAs.
+	Initiate CHILD_SA within existing IKE_SAs (always enabled for IKEv1).
 
 charon.routing_table
 	Numerical routing table to install routes to.
diff --git a/src/libcharon/sa/ike_sa_manager.c b/src/libcharon/sa/ike_sa_manager.c
index 3d1500909..908ce8191 100644
--- a/src/libcharon/sa/ike_sa_manager.c
+++ b/src/libcharon/sa/ike_sa_manager.c
@@ -1384,8 +1384,8 @@ METHOD(ike_sa_manager_t, checkout_by_config, ike_sa_t*,
 
 	DBG2(DBG_MGR, "checkout IKE_SA by config");
 
-	if (!this->reuse_ikesa)
-	{	/* IKE_SA reuse disable by config */
+	if (!this->reuse_ikesa && peer_cfg->get_ike_version(peer_cfg) != IKEV1)
+	{	/* IKE_SA reuse disabled by config (not possible for IKEv1) */
 		ike_sa = checkout_new(this, peer_cfg->get_ike_version(peer_cfg), TRUE);
 		charon->bus->set_sa(charon->bus, ike_sa);
 		return ike_sa;