deleted by author - commented on wrong post

I can confirm the Prolific 2303 64-bit driver works with IOGEAR adapters on Lioin & SL 64-bit.

As a side note, Keyspan has 64-bit drivers, also. I've confirmed they work with both Lion 64-bit and SL 64-bit.

I use the osx-pl2303.kext (242 KB) dated February 17, 2010 from BJA Electronics on my Lion install and it works fine with my Prolific based USB to Serial cable to control a Pix from the command line.

I tried this, but the driver didn't work for me. In my case, I installed the driver from failberg:

https://github.com/failberg/osx-pl2303

Note the warning: "A very unofficial fork of the Prolific PL2303 driver." However, this driver worked when the official driver did not.

Same experience here as johnalex. Official driver worked under Snow Leopard, but not under Lion. Although the driver was loaded (confirmed through About This Mac --> System Report --> USB), "Load My Tracks" could not find my Garmin GPS.

With this unofficial fork, it works fine again. I can't help but wonder for how long, though...