diff -Npru passenger-orig/ext/apache2/Configuration.cpp passenger-wc/ext/apache2/Configuration.cpp

--- passenger-orig/ext/apache2/Configuration.cpp	2012-03-05 17:33:31.162658085 -0800

+++ passenger-wc/ext/apache2/Configuration.cpp	2012-03-05 17:38:37.164628243 -0800

@@ -272,6 +272,7 @@ passenger_config_merge_dir(apr_pool_t *p

 DEFINE_SERVER_STR_CONFIG_SETTER(cmd_passenger_root, root)

 DEFINE_SERVER_STR_CONFIG_SETTER(cmd_passenger_ruby, ruby)

+DEFINE_SERVER_STR_CONFIG_SETTER(cmd_passenger_spawn_ipaddress, spawnIPAddress)

 DEFINE_SERVER_INT_CONFIG_SETTER(cmd_passenger_log_level, logLevel, unsigned int, 0)

 DEFINE_SERVER_STR_CONFIG_SETTER(cmd_passenger_debug_log_file, debugLogFile)

 DEFINE_SERVER_INT_CONFIG_SETTER(cmd_passenger_max_pool_size, maxPoolSize, unsigned int, 1)

@@ -474,6 +475,11 @@ const command_rec passenger_commands[] =

 		NULL,

 		RSRC_CONF,

 		"The Ruby interpreter to use."),

+	AP_INIT_TAKE1("PassengerSpawnIPAddress",

+		(Take1Func) cmd_passenger_spawn_ipaddress,

+		NULL,

+		RSRC_CONF,

+		"The IP address to bind to."),

 	AP_INIT_TAKE1("PassengerLogLevel",

 		(Take1Func) cmd_passenger_log_level,

 		NULL,

diff -Npru passenger-orig/ext/apache2/Configuration.hpp passenger-wc/ext/apache2/Configuration.hpp

--- passenger-orig/ext/apache2/Configuration.hpp	2012-03-05 17:33:31.162658085 -0800

+++ passenger-wc/ext/apache2/Configuration.hpp	2012-03-05 17:38:37.165628242 -0800

@@ -367,6 +367,9 @@ struct DirConfig {

 struct ServerConfig {

 	/** The filename of the Ruby interpreter to use. */

 	const char *ruby;

+

+	/** The IP Address to bind to. */

+	const char *spawnIPAddress;

 	/** The Passenger root folder. */

 	const char *root;

@@ -416,6 +419,7 @@ struct ServerConfig {

 	ServerConfig() {

 		ruby               = "ruby";

+		spawnIPAddress     = "127.0.0.1";

 		root               = NULL;

 		logLevel           = DEFAULT_LOG_LEVEL;

 		debugLogFile       = NULL;

diff -Npru passenger-orig/ext/apache2/HelperAgent.cpp passenger-wc/ext/apache2/HelperAgent.cpp

--- passenger-orig/ext/apache2/HelperAgent.cpp	2012-03-05 17:33:31.162658085 -0800

+++ passenger-wc/ext/apache2/HelperAgent.cpp	2012-03-05 17:38:37.165628242 -0800

@@ -245,7 +245,8 @@ public:

 			accountsDatabase, rubyCommand,

 			analyticsLogger,

 			options.getInt("log_level"),

-			options.get("debug_log_file", false)

+			options.get("debug_log_file", false),

+			options.get("spawn_ipaddress")

 		));

 		pool->setMax(maxPoolSize);

 		pool->setMaxPerApp(maxInstancesPerApp);

diff -Npru passenger-orig/ext/apache2/Hooks.cpp passenger-wc/ext/apache2/Hooks.cpp

--- passenger-orig/ext/apache2/Hooks.cpp	2012-03-05 17:33:31.162658085 -0800

+++ passenger-wc/ext/apache2/Hooks.cpp	2012-03-05 17:48:25.902486295 -0800

@@ -1401,7 +1401,8 @@ public:

 			serverConfig.unionStationGatewayCert,

 			serverConfig.unionStationProxyAddress,

 			serverConfig.unionStationProxyType,

-			serverConfig.prestartURLs);

+			serverConfig.prestartURLs,

+			serverConfig.spawnIPAddress);

 		analyticsLogger = ptr(new AnalyticsLogger(agentsStarter.getLoggingSocketAddress(),

 			"logging", agentsStarter.getLoggingSocketPassword()));

diff -Npru passenger-orig/ext/common/AgentsStarter.cpp passenger-wc/ext/common/AgentsStarter.cpp

--- passenger-orig/ext/common/AgentsStarter.cpp	2012-03-05 17:33:31.192658083 -0800

+++ passenger-wc/ext/common/AgentsStarter.cpp	2012-03-05 17:38:37.168628242 -0800

@@ -64,6 +64,7 @@ agents_starter_start(AgentsStarter *as,

                      const char *unionStationProxyAddress,

                      const char *unionStationProxyType,

                      const char **prestartURLs, unsigned int prestartURLsCount,

+                     const char *spawnIPAddress,

                      const AfterForkCallback afterFork,

                      void *callbackArgument,

                      char **errorMessage)

@@ -96,6 +97,7 @@ agents_starter_start(AgentsStarter *as,

 			unionStationProxyAddress,

 			unionStationProxyType,

 			setOfprestartURLs,

+			spawnIPAddress,

 			afterForkFunctionObject);

 		return 1;

 	} catch (const Passenger::SystemException &e) {

diff -Npru passenger-orig/ext/common/AgentsStarter.h passenger-wc/ext/common/AgentsStarter.h

--- passenger-orig/ext/common/AgentsStarter.h	2012-03-05 17:33:31.189658083 -0800

+++ passenger-wc/ext/common/AgentsStarter.h	2012-03-05 17:38:37.168628242 -0800

@@ -64,6 +64,7 @@ int  agents_starter_start(AgentsStarter

                           const char *unionStationProxyAddress,

                           const char *unionStationProxyType,

                           const char **prestartURLs, unsigned int prestartURLsCount,

+                          const char *spawnIPAddress,

                           const AfterForkCallback afterFork,

                           void *callbackArgument,

                           char **errorMessage);

diff -Npru passenger-orig/ext/common/AgentsStarter.hpp passenger-wc/ext/common/AgentsStarter.hpp

--- passenger-orig/ext/common/AgentsStarter.hpp	2012-03-05 17:33:31.190658083 -0800

+++ passenger-wc/ext/common/AgentsStarter.hpp	2012-03-05 17:38:37.169628242 -0800

@@ -387,6 +387,7 @@ public:

 	           const string &unionStationProxyAddress,

 	           const string &unionStationProxyType,

 	           const set<string> &prestartURLs,

+	           const string &spawnIPAddress,

 	           const function<void ()> &afterFork = function<void ()>())

 	{

 		TRACE_POINT();

@@ -416,6 +417,7 @@ public:

 			.setGid ("web_server_worker_gid", webServerWorkerGid)

 			.set    ("passenger_root",  passengerRoot)

 			.set    ("ruby",            rubyCommand)

+			.set    ("spawn_ipaddress",  spawnIPAddress)

 			.setInt ("max_pool_size",   maxPoolSize)

 			.setInt ("max_instances_per_app",     maxInstancesPerApp)

 			.setInt ("pool_idle_time",            poolIdleTime)

diff -Npru passenger-orig/ext/common/ApplicationPool/Pool.h passenger-wc/ext/common/ApplicationPool/Pool.h

--- passenger-orig/ext/common/ApplicationPool/Pool.h	2012-03-05 17:33:31.189658083 -0800

+++ passenger-wc/ext/common/ApplicationPool/Pool.h	2012-03-05 17:38:37.169628242 -0800

@@ -1062,7 +1062,8 @@ public:

 	     const string &rubyCommand = "ruby",

 	     const AnalyticsLoggerPtr &analyticsLogger = AnalyticsLoggerPtr(),

 	     int logLevel = 0,

-	     const string &debugLogFile = ""

+	     const string &debugLogFile = "",

+	     const string &spawnIPAddress = "127.0.0.1"

 	) : data(new SharedData()),

 		cstat(DEFAULT_MAX_POOL_SIZE),

 		lock(data->lock),

@@ -1079,7 +1080,7 @@ public:

 		this->spawnManager = ptr(new SpawnManager(spawnServerCommand, generation,

 			accountsDatabase, rubyCommand, analyticsLogger, logLevel,

-			debugLogFile));

+			debugLogFile, spawnIPAddress));

 		initialize(analyticsLogger);

 	}

diff -Npru passenger-orig/ext/common/SpawnManager.h passenger-wc/ext/common/SpawnManager.h

--- passenger-orig/ext/common/SpawnManager.h	2012-03-05 17:33:31.189658083 -0800

+++ passenger-wc/ext/common/SpawnManager.h	2012-03-05 17:38:37.170628241 -0800

@@ -107,6 +107,7 @@ private:

 	ServerInstanceDir::GenerationPtr generation;

 	AccountsDatabasePtr accountsDatabase;

 	string rubyCommand;

+	string spawnIPAddress;

 	AnalyticsLoggerPtr analyticsLogger;

 	int logLevel;

 	string debugLogFile;

@@ -267,6 +268,7 @@ private:

 			}

 			writeExact(ownerSocket, toString(logLevel) + "\n");

 			writeExact(ownerSocket, debugLogFile + "\n");

+			writeExact(ownerSocket, spawnIPAddress + "\n");

 			this->ownerSocket    = ownerSocket;

 			this->socketFilename = socketFilename;

@@ -547,13 +549,15 @@ public:

 	             const string &rubyCommand = "ruby",

 	             const AnalyticsLoggerPtr &analyticsLogger = AnalyticsLoggerPtr(),

 	             int logLevel = 0,

-	             const string &debugLogFile = ""

+	             const string &debugLogFile = "",

+	             const string &spawnIPAddress = "127.0.0.1"

 	) {

 		TRACE_POINT();

 		this->spawnServerCommand = spawnServerCommand;

 		this->generation  = generation;

 		this->accountsDatabase = accountsDatabase;

 		this->rubyCommand = rubyCommand;

+		this->spawnIPAddress = spawnIPAddress;

 		this->analyticsLogger = analyticsLogger;

 		this->logLevel = logLevel;

 		this->debugLogFile = debugLogFile;

diff -Npru passenger-orig/ext/common/Watchdog.cpp passenger-wc/ext/common/Watchdog.cpp

--- passenger-orig/ext/common/Watchdog.cpp	2012-03-05 17:33:31.189658083 -0800

+++ passenger-wc/ext/common/Watchdog.cpp	2012-03-05 17:38:37.170628241 -0800

@@ -75,6 +75,7 @@ static uid_t   webServerWorkerUid;

 static gid_t   webServerWorkerGid;

 static string  passengerRoot;

 static string  rubyCommand;

+static string  spawnIPAddress;

 static unsigned int maxPoolSize;

 static unsigned int maxInstancesPerApp;

 static unsigned int poolIdleTime;

@@ -592,7 +593,8 @@ protected:

 		options.set("request_socket_password", Base64::encode(requestSocketPassword)).

 			set("message_socket_password", Base64::encode(messageSocketPassword)).

 			set("logging_agent_address", loggingAgentAddress).

-			set("logging_agent_password", loggingAgentPassword);

+			set("logging_agent_password", loggingAgentPassword).

+			set("spawn_ipaddress", spawnIPAddress);

 		options.writeToFd(fd);

 	}

@@ -978,6 +980,7 @@ main(int argc, char *argv[]) {

 	webServerWorkerGid = agentsOptions.getGid("web_server_worker_gid");

 	passengerRoot = agentsOptions.get("passenger_root");

 	rubyCommand   = agentsOptions.get("ruby");

+	spawnIPAddress   = agentsOptions.get("spawn_ipaddress");

 	maxPoolSize        = agentsOptions.getInt("max_pool_size");

 	maxInstancesPerApp = agentsOptions.getInt("max_instances_per_app");

 	poolIdleTime       = agentsOptions.getInt("pool_idle_time");

diff -Npru passenger-orig/ext/nginx/ngx_http_passenger_module.c passenger-wc/ext/nginx/ngx_http_passenger_module.c

--- passenger-orig/ext/nginx/ngx_http_passenger_module.c	2012-03-05 17:33:31.188658083 -0800

+++ passenger-wc/ext/nginx/ngx_http_passenger_module.c	2012-03-05 17:38:37.171628240 -0800

@@ -291,6 +291,7 @@ start_helper_server(ngx_cycle_t *cycle)

         union_station_proxy_address,

         union_station_proxy_type,

         (const char **) prestart_uris_ary, passenger_main_conf.prestart_uris->nelts,

+        "127.0.0.1",

         starting_helper_server_after_fork,

         cycle,

         &error_message);

diff -Npru passenger-orig/helper-scripts/passenger-spawn-server passenger-wc/helper-scripts/passenger-spawn-server

--- passenger-orig/helper-scripts/passenger-spawn-server	2012-03-05 17:33:31.193658083 -0800

+++ passenger-wc/helper-scripts/passenger-spawn-server	2012-03-05 17:38:37.171628240 -0800

@@ -47,6 +47,7 @@ begin

 		node_name = owner_socket.readline.strip

 		log_level = owner_socket.readline.to_i

 		debug_log_file = owner_socket.readline.strip

+		spawn_ipaddress = owner_socket.readline.strip

 	rescue EOFError

 		exit

 	end

@@ -93,6 +94,8 @@ begin

 			"node_name" => node_name

 		}

 	end

+

+	options["spawn_ipaddress"] = spawn_ipaddress

 	require 'phusion_passenger/spawn_manager'

 	spawn_manager = PhusionPassenger::SpawnManager.new(options)

diff -Npru passenger-orig/lib/phusion_passenger/abstract_request_handler.rb passenger-wc/lib/phusion_passenger/abstract_request_handler.rb

--- passenger-orig/lib/phusion_passenger/abstract_request_handler.rb	2012-03-05 17:33:31.159658087 -0800

+++ passenger-wc/lib/phusion_passenger/abstract_request_handler.rb	2012-03-05 17:38:37.172628240 -0800

@@ -174,11 +174,11 @@ class AbstractRequestHandler

 			@main_socket_address, @main_socket = create_unix_socket_on_filesystem

 			@server_sockets[:main] = [@main_socket_address, 'unix', @main_socket]

 		else

-			@main_socket_address, @main_socket = create_tcp_socket

+			@main_socket_address, @main_socket = create_tcp_socket(options["spawn_ipaddress"])

 			@server_sockets[:main] = [@main_socket_address, 'tcp', @main_socket]

 		end

-		@http_socket_address, @http_socket = create_tcp_socket

+		@http_socket_address, @http_socket = create_tcp_socket(options["spawn_ipaddress"])

 		@server_sockets[:http] = [@http_socket_address, 'tcp', @http_socket]

 		@owner_pipe = owner_pipe

@@ -397,13 +397,14 @@ private

 		end

 	end

-	def create_tcp_socket

+	def create_tcp_socket(spawn_ipaddr = nil)

 		# We use "127.0.0.1" as address in order to force

 		# TCPv4 instead of TCPv6.

-		socket = TCPServer.new('127.0.0.1', 0)

+		spawn_ipaddr ||= '127.0.0.1'

+		socket = TCPServer.new(spawn_ipaddr, 0)

 		socket.listen(BACKLOG_SIZE)

 		socket.close_on_exec!

-		socket_address = "127.0.0.1:#{socket.addr[1]}"

+		socket_address = "#{spawn_ipaddr}:#{socket.addr[1]}"

 		return [socket_address, socket]

 	end