SSL data capture

I want to know what is wrong with this irule?

when CLIENTSSL_HANDSHAKE {

Trigger collection of the decrypted payload once the SSL handshake has been completed successfully SSL::collect }

when CLIENTSSL_DATA {

log local4. "[[SSL::payload 6 10] [SSL::payload 300 50] client [IP::client_addr]]" Release the payload SSL::release }

I am getting an error saying that 'SSL::payload 300 50' is invalid?

thanks