def verify(data, sig)
      regenerate_pubkey unless @key.public_key
      sig = Bitcoin::OpenSSL_EC.repack_der_signature(sig)
      if sig
        @key.dsa_verify_asn1(data, sig)
      else
        false
      end
    end
def verify(data, sig)
      regenerate_pubkey unless @key.public_key
      sig = Bitcoin::OpenSSL_EC.repack_der_signature(sig)
      if sig
        @key.dsa_verify_asn1(data, sig)
      else
        false
      end
    end
Verify signature +sig+ for +data+.
  key2 = Bitcoin::Key.new(nil, key1.pub)
  key2.verify("some data", sig)