Java Cryptography Architecture is a pluggable framework. This means
    users can plug in different JCA providers in their environment.
    Currently, registered security providers are available to all applications
    running on the same VM instance. And one must register a security
    provider before using it. In order to register a security provider,
    one has to have approriate permissions or update the java.security
    file - this becomes an issue in deployment. Many users have found 
    that it would be very useful if an application/applet can access a 
    provider within its own space (note: not making that provider available 
    to other applications running on the same VM instance) without any 
    special security permissions.

    This method has already been added for the existing engine classes
    in J2SE. This RFE adds the method to the JCE engine classes:

       javax.crypto.Cipher
       javax.crypto.KeyAgreement
       javax.crypto.Mac
       javax.crypto.KeyGenerator
       javax.crypto.SecretKeyFactory
       javax.crypto.ExemptionMechanism