A DESCRIPTION OF THE REQUEST :
There's no way for a third party to provide support for new signature algorithms without creating an entirely new JSR 105 implementation.

JUSTIFICATION :
As it stands, the JSR 105 API provides no means for third parties to provide implementations of new SignatureMethod algorithms or new elements for use within KeyInfo. The only recourse for such third parties is for them to implement XMLSignatureFactory and KeyInfoFactory and everything they provide. This is a significant duplication of effort.