public async Task<PostmarkCompleteSenderSignature> UpdateSignatureAsync
(int signatureId, string name = null, string replyToEmail = null, string returnPathDomain = null)
{
var parameters = new Dictionary<string, object>();
parameters["Name"] = name;
parameters["ReplyToEmail"] = replyToEmail;
parameters["ReturnPathDomain"] = returnPathDomain;
return await this.ProcessRequestAsync<Dictionary<string, object>, PostmarkCompleteSenderSignature>
("/senders/" + signatureId, HttpMethod.Put, parameters);
}