ZyXEL "Omni 288S" MODEM firmware v1.21/v3.02:

 model name  description  filename
Handbuch release notes of all releases incl. v3.01 os__301.txt
O288S V.34 Firmware for Omni 288s - V.34 os__121.zip
Drivers V.34 Driver for Windows 9x - V.34 mdmzyxos.zip
O288S V.90 Firmware for Omni 288s - V.34 & V.90 os__302.zip
Drivers V.90 Driver for Windows 9x - V.34 & V.90
Driver for Windows NT 4.x - V.34 & V.90
mdmzos90.zip
mdmzos90.zip