Verizon PCMCIA Card Just Works
Apple God writes "I was a friend's house and he showed me his Verizion PCMCIA card for internet access. On a whim, I put it in my PowerBook, and it recognized the card and prompted me for authorization to configure the system for use with the card. I entered my password, and was surprised to see an icon in the menu bar for it. I clicked on this icon and selected connect, it worked! I had internet access. Here is a picture of the card that I used. When we checked Verizon's page, they only listed Windows compatibility. To make matters sweeter, my friend was shocked that it 'just worked' because he had to install drivers in XP before it would work."
http://www.apple.com/support/downloads/verizonbroa dbandaccesssupport.html
Were you running 10.3.5? Since those drivers were released a month before 10.3.5, I suspect they were included in it, and that would explain the card "just work"ing.
FWIW
I believe the Verizon drivers (/System/Library/CoreServices/Menu Extras/Verizon.menu, /System/Library/Extensions/IOSerialFamily.kext/Con tents/PlugIns/AppleVerizonSupport.kext) first were included in 10.2, but don't recall for sure. (AC 'cause I'm Apple.)