Did you run 'modeswitch' before trying to set up the connection?
I think you may need to, to make the modem visible in Linux.
Yes, I've been running usb_modeswitch for every try. Also, I didn't know if it mattered so I uncommented the operational lines in etc/usb_modeswitch.conf. When I run modeswitch I get:
[typed because it's on the other machine]
Looking for target devices ...
No devices in target mode or class found
Looking for default devices ...
Found default devices (1)
Accessing device 003 on bus 002 ...
Using endpoints 0x08 (out) and 0x87 (in)
Inquiring device details; driver will be detached ...
Looking for active driver ...
OK, driver found ("usbfs")
OK, driver "usbfs" detached
[Can't believe I'm typing all this but...]
Bus 001 Device 003: ID 0ace:1211 ZyDAS 802.11bg
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 003: ID 1f28:0021
Bus 002 Device 002: ID 03f0:4911 Hewlett-Packard PSC 2350
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 2.0 root hub
When I saw these entries I expected the thing to work. No joy yet but I must be getting close. Probably need an adjustment to GNOME PPP.