Bouncy Castle doesn't supports ELGAMAL_ENCRYPT for message signing

Question

Hi,

I am using BouncyCastle library for cryptography. I was using DSA/RSA keys initially to transfer the message and it was all working fine

Now I have to switch to DSA + ElGamal key pair for the signing/encryption of the message. but it doesn't seems to be working.

The first step that I perform before sending the message is signing. here is the snippet

...
PGPSignatureGenerator signer = new PGPSignatureGenerator(signingKey.getPublicKey().getAlgorithm(), PGPUtil.SHA256, PgpConfigurationData.BOUNCE_CASTLE_NAME);
...

where signingKey is the secret key. The "signingKey.getPublicKey().getAlgorithm()" return 16 , which is basically evaluates to "ELGAMAL_ENCRYPT" and an exception is thrown "no such algorithm: SHA256withElGamal for provider BC"

....
case PublicKeyAlgorithmTags.ELGAMAL_ENCRYPT: // in some malformed cases.
case PublicKeyAlgorithmTags.ELGAMAL_GENERAL:
            encAlg = "ElGamal";
            break;
default:
            throw new PGPException("unknown algorithm tag in signature:" + keyAlgorithm);
....        

I am using the gpg --gen-key utility in unix . The option that is gives during key creation are

• (1) DSA and Elgamal (default)
• (2) DSA (sign only)
• (5) RSA (sign only

)

I don't understand where is the problem , Am I generation the keys incorrectly or do I have to switch to some other provider.

Thanks!