I couldn't get the EVDO card to work under Jaunty on my Latitude E5400. Now I've upgraded to Lucid on E6510, and PC5750 is a piece of cake... well, almost.
After I inserted the card, I got a bunch of evbug.c messages in dmesg, and no ttyACM0 to use. A little search got me to blacklist evbug. I plugged in the card again, and noticed there's an option "Enable Mobile Broadband" in Network Manager. So I did it and chose Verizon as the provider That's it! IP address was set right away and I got online in no time, no pesky VZ Access Manager required. In fact, I'm writing this post with that connection. :)