The public key certificate for the MDN receipt signature.
getReceiptSignerCert(): Certificate; setReceiptSignerCert(receiptSignerCert: Certificate): void;
Ordinarily, if your trading partner uses the same certificate for both signing and encryption, the certificate specified in RecipientCert is used for both encryption and verifying the receipt signature.
If your trading partner uses different certificates for signing and encryption, you must set this property to the public key for you partner's signing certificate before invoking Post.
If set, this property should be a public key instance of Certificate.