Mono missing ClientCertificates for X509CertificateCollection. Is there someway to add it?

Hello,
I am wondering if there are any assets or libraries out there that can add some needed functionality that Mono seems to be missing in regards to using X509 client certificates. I am getting this error :

Code (CSharp):

1. NotImplementedException: The method or operation is not implemented.
2. at System.Net.Http.HttpClientHandler.get_ClientCertificates () [0x00000] in <20a8f293e89843148f03a963627efba4>:0
3. at Raven.Client.Http.RequestExecutor.CreateHttpMessageHandler (System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, System.Boolean setSslProtocols, System.Boolean useCompression, System.Boolean hasExplicitlySetCompressionUsage) [0x00075] in <3af6f962c10f46e297126f8db0cace22>:0

Looking through Monos github, line 429 of System.Net.Http/System.Net.Http/HttpClientHandler.cs shows this, unfortunately.

Code (CSharp):

1.         public X509CertificateCollection ClientCertificates {
2.             get {
3.                 throw new NotImplementedException ();
4.             }
5.         }

So I was hoping that perhaps someone might know of something out there that might be able to give me the missing functionality that I am needing?

Thanks for any assistance you are able to provide!
-MH