How can I delete stored messages from Telstra 7100a cordless phone?

I've lost my Telstra 7100a cordless phone manual and need to delete the stored messages, does anyone know how to do this? The phone "message bank full" red light is flashing. I've checked www.telstra.com for the manual but the link to the 7100a .pdf manual leads nowhere. The phone is giving all my callers a message telling them they can't leave a message - without telling me that this is happening! Lucky someone let me know!