There is a way, but I haven't heard of anyone doing it yet. Since what makes Sony's HDD work with the games is their custom firmware, replacing the firmware of your hard drive with one that is functionally the same as Sony's would do the trick. Of course, such a firmware would have to be made for your specific hard drive model first, and then a way to install it over the default firmware would have to be used.
Originally Posted by NightmanDSS
That said, it's definitely possible, but who's going to bother doing it for many models of hard drives with how little HDD support there is in non-Japanese games?
My PlayStation2 HDD guide.
NTSC J SCPH 30000 with HDD and PSBBN 0.32
NTSC U/C SCPH 30001R Astral Blue LE PS2
Final Fantasy XI status:
Server - Ragnarok, Race - Mithra, Jobs - BLM 72 WHM 51 SCH 39 SMN 25, Nationality - Windurst, Name - Bungiefan