Well!!! I tried to load a PS2 game with a retro-compatible 60 gb PS3 with the same method but when I load PS2emu.self it run 2/3 seconds and then it return to Sony XMB. I think that with a small effort we can play PS1 and PS2 games directly from MULTIMAN
in theory shouldn't it be rather simple to boot psx isos? like create a "ps3 disc image" structure with the additional content of the psx game so that you can mount it like any other game then use filemanager to open that self and it should just grab the needed files from the emulated drive?
only problem i could think of is difference in filesystem betweend psx cd and ps3 bd but maybe it doesn't even matter?
reminds me of old psp scene days where every grp had to release psx games repacked to psp format... since there don't seem to be any "security check" on ps1emu i guess it could work?