A DESCRIPTION OF THE REQUEST :
We would like to specify a Signature Provider object that is not registered in the provider list. But for the available method verify(PublicKey key, String sigProvider) the named Provider must be registered.

JUSTIFICATION :
The classes CertificateFactory and Signature each have the method getInstance(String type/algorithm, Provider provider) with a Provider object that does not have to be registered. It is inconsistent that Certificate.verify does not support all variants of Signature.getInstance.
In a servlet container like tomcat it is critical to register a Provider that is not defined outside the web applications since each web application has its own class loader. A second web application cannot register the Provider again although the classes would be different. Log messages of the Provider should appear in the log file of the specific web application.