diff --git a/extensions/Makefile.am b/extensions/Makefile.am
index 5fe872dd2..aed842ca1 100644
--- a/extensions/Makefile.am
+++ b/extensions/Makefile.am
@@ -9,6 +9,7 @@ extension_LTLIBRARIES =		\
   chantype_dummy.la		\
   chm_adminonly.la		\
   chm_operonly.la		\
+  chm_serviceonly.la		\
   chm_insecure.la		\
   chm_nonotice.la		\
   chm_operpeace.la		\
diff --git a/extensions/chm_serviceonly.c b/extensions/chm_serviceonly.c
new file mode 100644
index 000000000..dda2cc63b
--- /dev/null
+++ b/extensions/chm_serviceonly.c
@@ -0,0 +1,56 @@
+#include "stdinc.h"
+#include "modules.h"
+#include "hook.h"
+#include "client.h"
+#include "ircd.h"
+#include "send.h"
+#include "s_conf.h"
+#include "s_user.h"
+#include "s_serv.h"
+#include "numeric.h"
+#include "chmode.h"
+
+static const char chm_serviceonly_desc[] =
+	"Adds channel mode +X which makes a channel service-only";
+
+static void h_can_join(void *);
+
+mapi_hfn_list_av1 serviceonly_hfnlist[] = {
+	{ "can_join", h_can_join },
+	{ NULL, NULL }
+};
+
+static unsigned int mymode;
+
+static int
+_modinit(void)
+{
+	mymode = cflag_add('X', chm_staff);
+	if (mymode == 0)
+		return -1;
+
+	return 0;
+}
+
+
+static void
+_moddeinit(void)
+{
+	cflag_orphan('X');
+}
+
+DECLARE_MODULE_AV2(chm_serviceonly, _modinit, _moddeinit, NULL, NULL, serviceonly_hfnlist, NULL, NULL, chm_serviceonly_desc);
+
+static void
+h_can_join(void *data_)
+{
+	hook_data_channel *data = data_;
+	struct Client *source_p = data->client;
+	struct Channel *chptr = data->chptr;
+
+	if((chptr->mode.mode & mymode) && !IsService(source_p)) {
+		sendto_one_numeric(source_p, 520, "%s :Cannot join channel (+X) - you are not a service", chptr->chname);
+		data->approved = ERR_CUSTOM;
+	}
+}
+