Project Tasks - can you have different per hour rates for different tasks (Australian Version)

Project Tasks - can you have different per hour rates for different tasks (Australian Version)

I have a client to whom I have multiple tasks:
1. Admin @ $60.00 per hour

2. Telephonist, which I want to invoice at $30.00
     
It looks like ZOHO Projects only allows for one charge-out rate; this is correct or am I missing something?