For the people who don't follow the 'ESI Juli@' thread, drivers for the following cards are available for OSX10.5 and 10.6 (64-bit):

Envy24:
Terratec Aureon Sky
Terratec Aureon Space
Terratec Phase 22
Terratec Phase 28
M-Audio Revolution 5.1
M-Audio Revolution 7.1
M-Audio Audiophile 192
ESI Juli@
Audiotrak 7.1
Audiotrak Prodigy HD2

Envy24HT:
M-Audio Delta 44
M-Audio Delta 66
M-Audio Delta 410
M-Audio Delta 2496
M-Audio Delta 1010
M-Audio Delta 1010LT
Terratec Phase 88 / EWS88MT / TS88PCI
Terratec EWX2496

You can find drivers here.