diff --git a/include/s_serv.h b/include/s_serv.h
index 73327c70..c8c3328b 100644
--- a/include/s_serv.h
+++ b/include/s_serv.h
@@ -73,13 +73,14 @@ struct Capability
 #define CAP_EUID	0x80000 /* supports EUID (ext UID + nonencap CHGHOST) */
 #define CAP_EOPMOD	0x100000 /* supports EOPMOD (ext +z + ext topic) */
 #define CAP_BAN		0x200000 /* supports propagated bans */
+#define CAP_BAN		0x400000 /* supports MLOCK messages */
 
 #define CAP_MASK        (CAP_QS  | CAP_EX   | CAP_CHW  | \
                          CAP_IE  | CAP_KLN  | CAP_SERVICE |\
                          CAP_CLUSTER | CAP_ENCAP | \
                          CAP_ZIP  | CAP_KNOCK  | CAP_UNKLN | \
 			 CAP_RSFNC | CAP_SAVE | CAP_EUID | CAP_EOPMOD | \
-			 CAP_BAN)
+			 CAP_BAN | CAP_MLOCK)
 
 #ifdef HAVE_LIBZ
 #define CAP_ZIP_SUPPORTED       CAP_ZIP
diff --git a/src/s_serv.c b/src/s_serv.c
index 90f2c6c2..1a4705cd 100644
--- a/src/s_serv.c
+++ b/src/s_serv.c
@@ -89,6 +89,7 @@ struct Capability captab[] = {
 	{ "EUID",	CAP_EUID },
 	{ "EOPMOD",	CAP_EOPMOD },
 	{ "BAN",	CAP_BAN },
+	{ "MLOCK",	CAP_MLOCK },
 	{0, 0}
 };