The contract seems to be working flawlessly. The 5th payment just came in and it split it .25 each to the previous 4 addresses.

See it on the blockchain:
http://etherscan.io/address/0x3325439082FF8ba7371DFdAa1AF297bBfcAc21b2#internaltx

One person tried to send .001 ETH and another person tried to sent 20ETH from a contract.
Both of these transactions were rejected and returned, the contract only will accept 1 ETH.