--- a/plugins/mod_admin_telnet.lua	Thu Apr 10 13:13:07 2014 +0200
+++ b/plugins/mod_admin_telnet.lua	Thu Apr 10 13:15:11 2014 +0200
@@ -896,6 +896,9 @@
 
 function def_env.muc:create(room_jid)
 	local room, host = check_muc(room_jid);
+	if not room_name then
+		return room_name, host;
+	end
 	if not room then return nil, host end
 	if hosts[host].modules.muc.rooms[room_jid] then return nil, "Room exists already" end
 	return hosts[host].modules.muc.create_room(room_jid);
@@ -903,6 +906,9 @@
 
 function def_env.muc:room(room_jid)
 	local room_name, host = check_muc(room_jid);
+	if not room_name then
+		return room_name, host;
+	end
 	local room_obj = hosts[host].modules.muc.rooms[room_jid];
 	if not room_obj then
 		return nil, "No such room: "..room_jid;

--- a/prosody	Thu Apr 10 13:13:07 2014 +0200
+++ b/prosody	Thu Apr 10 13:15:11 2014 +0200
@@ -49,9 +49,6 @@
 
 -- Check dependencies
 local dependencies = require "util.dependencies";
-if not dependencies.check_dependencies() then
-	os.exit(1);
-end
 
 -- Load the config-parsing module
 config = require "core.configmanager"
@@ -116,6 +113,12 @@
 	end
 end
 
+function check_dependencies()
+	if not dependencies.check_dependencies() then
+		os.exit(1);
+	end
+end
+
 function load_libraries()
 	-- Load socket framework
 	server = require "net.server"
@@ -382,6 +385,7 @@
 sanity_check();
 sandbox_require();
 set_function_metatable();
+check_dependencies();
 load_libraries();
 init_global_state();
 read_version();

--- a/util/dependencies.lua	Thu Apr 10 13:13:07 2014 +0200
+++ b/util/dependencies.lua	Thu Apr 10 13:15:11 2014 +0200
@@ -49,6 +49,14 @@
 end;
 
 function check_dependencies()
+	if _VERSION ~= "Lua 5.1" then
+		print "***********************************"
+		print("Unsupported Lua version: ".._VERSION);
+		print("Only Lua 5.1 is supported.");
+		print "***********************************"
+		return false;
+	end
+
 	local fatal;
 
 	local lxp = softreq "lxp"