mod-mono-server 4 is not working, while 2 does

I need to deploy an ASP.NET MVC4 (MVC3 at least) application on Centos 6 server. I've installed Mono 3.2.1, XSP4, mod_mono (for use with apache web server) and succesfully ran the test application that goes with mono. I used a config tool to create a config for app directory and deployed an empty ASP.NET WebPages project created in VS2012 on .Net 2.0 - it ran ok. But I need to run an .net 4.5 or at least 4.0 application, so I've set the MonoServerPath to mod-mono-server4 instead of mod-mono-server2 in the config, but now i'm getting a "Service Temporarily Unavailable" error while trying to access the asp.net project directory (even empty). What should I check for? **Update:** I checked the apache log and here what it shows: mod-mono-server4 Exception caught during reading the configuration file: System.MissingMethodException: Method not found: 'System.Configuration.IConfigurationSectionHandler.Create'. at System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection (System.String configKey) [0x00000] in :0 at System.Configuration.ConfigurationManager.GetSection (System.String sectionName) [0x00000] in :0 at System.Configuration.ConfigurationManager.get_AppSettings () [0x00000] in :0 at Mono.WebServer.Apache.Server.get_AppSettings () [0x00001] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:208 at Mono.WebServer.Apache.Server+ApplicationSettings..ctor () [0x0002a] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:63 mod-mono-server4 Listening on: /tmp/mod_mono_server_Unreal Root directory: /var/www/html/Unreal Error: An exception was thrown by the type initializer for System.Net.Sockets.Socket mod-mono-server4 Exception caught during reading the configuration file: System.MissingMethodException: Method not found: 'System.Configuration.IConfigurationSectionHandler.Create'. at System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection (System.String configKey) [0x00000] in :0 at System.Configuration.ConfigurationManager.GetSection (System.String sectionName) [0x00000] in :0 at System.Configuration.ConfigurationManager.get_AppSettings () [0x00000] in :0 at Mono.WebServer.Apache.Server.get_AppSettings () [0x00001] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:208 at Mono.WebServer.Apache.Server+ApplicationSettings..ctor () [0x0002a] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:63 mod-mono-server4 Listening on: /tmp/mod_mono_server_Unreal Root directory: /var/www/html/Unreal Error: An exception was thrown by the type initializer for System.Net.Sockets.Socket mod-mono-server4 Exception caught during reading the configuration file: System.MissingMethodException: Method not found: 'System.Configuration.IConfigurationSectionHandler.Create'. at System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection (System.String configKey) [0x00000] in :0 at System.Configuration.ConfigurationManager.GetSection (System.String sectionName) [0x00000] in :0 at System.Configuration.ConfigurationManager.get_AppSettings () [0x00000] in :0 at Mono.WebServer.Apache.Server.get_AppSettings () [0x00001] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:208 at Mono.WebServer.Apache.Server+ApplicationSettings..ctor () [0x0002a] in /usr/src/xsp-2.10.2/src/Mono.WebServer.Apache/main.cs:63 mod-mono-server4 Listening on: /tmp/mod_mono_server_Unreal Root directory: /var/www/html/Unreal Error: An exception was thrown by the type initializer for System.Net.Sockets.Socket [Wed Sep 25 08:45:13 2013] [error] Failed to connect to mod-mono-server after several attempts to spawn the process.