According to the North American PS3 website all you will need to transfer your PS2/PSone saved data to the PS3 is a memory card adapter:
To use saved data on a PS2 memory card, you must copy the data onto a virtual memory card within the hard disk. This requires a PS2/PSone memory card adapter to [...]
"Sony Reveals How to Transfer PS2 Data to PS3" - 05.08.06