||About Prolific PL-2303 driver for 64 bit Mac OS X
Enhanced PL2303 USB to Serial Driver for Mac OS X to be 64 bit compatible. The kernel extension compiles into an Universal Binary which can be loaded in Snow Leopard 32 and 64 bit mode. This driver is based on version 0.3.1 of the original 32 bit driver is available.
Usage: Download the file, if necessary extract the .zip file, then copy the .kext into the directory /System/Library/Extensions and reboot.