FT-232R issues

I have a USB GPS/TNC (terminal node controller) with a USB interface that reports itself as an FT-232R or 232RL (is there a difference?) I get /dev/ttyUSB0, but nothing functions. I can open the port, but don't see any data going across it.

Just to be sure, I've tried Raspbian and Debian Squeeze, Fedora Remix 14 I had issues booting.

Any suggestions?

Thanks,
Kevin

reports itself as an FT-232R or 232RL (is there a difference?) I get /dev/ttyUSB0, but nothing functions.

FT232RL's have been proven to work for others here:
viewtopic.php?f=44&t=8010

Thanks yes I saw that others with this had success, however, I haven't.

This GPS/tnc thing I have works fine in hrm I actually don't know what version of Linux I have on my USB stick, but it's from 2008, and it works fine out of the box. It's recognized by the Pi, it gets assigned /dev/ttyUSB0, but it doesn't actually communicate.

FT232R is a common name. FT232RL is compact 28-Lead SSOP and FT232RQ QFN-32 package