HTTPs problem Error code 0x5

Hi people,

I have a problem to access HTTPs service using an RestSharp library (http://components.xamarin.com/view/restsharp/).

Always i try to send request, i receive this error:

ErrorException  {System.Net.WebException: Error: SendFailure (Error writing headers) 
---> System.Net.WebException: Error writing headers 
---> System.IO.IOException: The authentication or decryption has failed. 
---> Mono.Security.Protocol.Tls.TlsException: Invalid certificate received from server. Error code: 0x5   
at Mono.Security.Protocol.Tls.Handshake.Client.TlsServerCertificate.RemoteValidation (Mono.Security.Protocol.Tls.ClientContext context, AlertDescription description) [0x00084] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Client/TlsServerCertificate.cs:224    
at Mono.Security.Protocol.Tls.Handshake.Client.TlsServerCertificate.validateCertificates (Mono.Security.X509.X509CertificateCollection certificates) [0x0000f] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Client/TlsServerCertificate.cs:193    
at Mono.Security.Protocol.Tls.Handshake.Client.TlsServerCertificate.ProcessAsTls1 () [0x00054] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake.Client/TlsServerCertificate.cs:105    
at Mono.Security.Protocol.Tls.Handshake.HandshakeMessage.Process () [0x00037] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls.Handshake/HandshakeMessage.cs:105    
at Mono.Security.Protocol.Tls.ClientRecordProtocol.ProcessHandshakeMessage (Mono.Security.Protocol.Tls.TlsStream handMsg) [0x00039] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/ClientRecordProtocol.cs:81    
at Mono.Security.Protocol.Tls.RecordProtocol.InternalReceiveRecordCallback (IAsyncResult asyncResult) [0x00123] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs:397    
--- End of inner exception stack trace ---   
at Mono.Security.Protocol.Tls.SslClientStream.EndNegotiateHandshake (IAsyncResult result) [0x00035] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs:425    
at Mono.Security.Protocol.Tls.SslStreamBase.AsyncHandshakeCallback (IAsyncResult asyncResult) [0x0000c] 
in /Developer/MonoTouch/Source/mono/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslStreamBase.cs:99    
--- End of inner exception stack trace ---   
--- End of inner exception stack trace ---   
at System.Net.HttpWebRequest.EndGetRequestStream (IAsyncResult asyncResult) [0x00043] 
in /Developer/MonoTouch/Source/mono/mcs/class/System/System.Net/HttpWebRequest.cs:847    
at System.Net.HttpWebRequest.GetRequestStream () [0x00057] in /Developer/MonoTouch/Source/mono/mcs/class/System/System.Net/HttpWebRequest.cs:865    
at RestSharp.Http.WriteRequestBody (System.Net.HttpWebRequest webRequest) [0x00000] in <filename unknown>:0    
at RestSharp.Http.PostPutInternal (System.String method) [0x00000] in <filename unknown>:0    
at RestSharp.Http.AsPost (System.String httpMethod) [0x00000] in <filename unknown>:0    
at RestSharp.RestClient.DoExecuteAsPost (IHttp http, System.String method) [0x00000] in <filename unknown>:0    
at RestSharp.RestClient.Execute (IRestRequest request, System.String httpMethod, System.Func 3 getResponse) [0x00000] in <filename unknown>:0 }    
System.Net.WebException

When i access with browsers Chrome/Internet Explorer/Firefox does not give error.

Attached is some information on the certificate.