private long decryptBlockCBC(long lCipherblock)
        {
            // save the current block
            long lTemp = lCipherblock;

            // decrypt the block
            lCipherblock = super.decryptBlock(lCipherblock);

            // dechain the block
            lCipherblock ^= m_lCBCIV;

            // set the new CBC IV
            m_lCBCIV = lTemp;

            // return the decrypted block
            return lCipherblock;
        }
cleans up all critical internals,
call this if you don't need an instance anymore
xmppserver/src/main/java/org/jivesoftware/util/Blowfish.java