--- a/core/configmanager.lua	Fri Jul 25 13:53:39 2014 +0100
+++ b/core/configmanager.lua	Thu Jul 31 06:56:21 2014 +0100
@@ -17,6 +17,9 @@
 local deps = require"util.dependencies";
 local path_sep = package.config:sub(1,1);
 
+local have_encodings, encodings = pcall(require, "util.encodings");
+local nameprep = have_encodings and encodings.stringprep.nameprep or function (host) return host:lower(); end
+
 module "configmanager"
 
 local parsers = {};
@@ -170,6 +173,7 @@
 		
 		rawset(env, "__currenthost", "*") -- Default is global
 		function env.VirtualHost(name)
+			name = nameprep(name);
 			if rawget(config, name) and rawget(config[name], "component_module") then
 				error(format("Host %q clashes with previously defined %s Component %q, for services use a sub-domain like conference.%s",
 					name, config[name].component_module:gsub("^%a+$", { component = "external", muc = "MUC"}), name, name), 0);
@@ -187,6 +191,7 @@
 		env.Host, env.host = env.VirtualHost, env.VirtualHost;
 		
 		function env.Component(name)
+			name = nameprep(name);
 			if rawget(config, name) and rawget(config[name], "defined") and not rawget(config[name], "component_module") then
 				error(format("Component %q clashes with previously defined Host %q, for services use a sub-domain like conference.%s",
 					name, name, name), 0);