diff --git a/modules/core/m_nick.c b/modules/core/m_nick.c
index 0b2481e4..09d34df8 100644
--- a/modules/core/m_nick.c
+++ b/modules/core/m_nick.c
@@ -122,7 +122,7 @@ mr_nick(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_
 	struct Client *target_p;
 	char nick[NICKLEN];
 
-	if (strlen(client_p->id) == 3)
+	if (strlen(client_p->id) == 3 || (source_p->preClient && !EmptyString(source_p->preClient->id)))
 	{
 		exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
 		return;
diff --git a/modules/m_sasl.c b/modules/m_sasl.c
index 284e4c93..c76d6aab 100644
--- a/modules/m_sasl.c
+++ b/modules/m_sasl.c
@@ -146,7 +146,7 @@ m_authenticate(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *
 		return;
 	}
 
-	if(strlen(client_p->id) == 3)
+	if (strlen(client_p->id) == 3 || (source_p->preClient && !EmptyString(source_p->preClient->id)))
 	{
 		exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
 		return;
diff --git a/modules/m_user.c b/modules/m_user.c
index d0360039..fc657c9b 100644
--- a/modules/m_user.c
+++ b/modules/m_user.c
@@ -63,7 +63,7 @@ mr_user(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_
 	static char buf[BUFSIZE];
 	char *p;
 
-	if (strlen(client_p->id) == 3)
+	if (strlen(client_p->id) == 3 || (source_p->preClient && !EmptyString(source_p->preClient->id)))
 	{
 		exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
 		return;