Lantronix power supply 3.3V or 5V?

In my sojourn through Tom Igoe’s book, Making Things Talk, I came to the Lantronix Xport.

The book says to connect the Xport Vdd to a 5V source, and page 119 shows it connected directly to the output of a 7805 regulator. However, Lantronix’ site and everywhere else says the Xport needs 3.3V. Ref: page 4, where it says Vcc should be 3.14, 3.3, or 3.46V min, nominal and max, respectively.

Is the Xport capable of running off 5V after all? Any info appreciated.

Thanks in advance,

I used a Lantronix converter at my last place of employment and it was a 3V3 device. I have noticed a few errors in that book, like his explanation of how GPS fundamentally works.