The payment address is tied to your request - you can pay into it in as many transactions as you like. Only after the work is finished and the payment is sent to the miner, will your extra transactions be ignored. You can try sending in two 0.01BTC transactions to start and see if the reward increases once the transactions are confirmed. If you come across any problems, just let me know.
Okay, sorry about that - pool's memory cache didn't flush properly. A proper bounty is appearing now (0.064 - 80% of 0.08 as per norm). I will add memory clearing functionality for that use case to my TODO list.
Wait so I need to pay 0.02 BTC more to get to the minimum 0.08 BTC requirement for an address with 8 specified characters? I wish I was notified first. Please clarify before I deposit such an amount.