USR5637 USB setup

Hello, I am abandoning the (un-successful) search for the software driver
for the internal (software) hsfmodem on my Dell 1420 notebook (shame Dell
and Linuxant), have purchased and received a new USR5637 USB connected
processor modem and made some progress on using this dial-up modem.
Wvdial does now recognize the modem after linking /dev/modem to the
target /dev/ttyACM0.

# ln -T /dev/ttyACM0 /dev/modem

The USR5637 modem does now indeed connect, evidence login negotiation for
username and password and return of PPP session #, IP address, MTU.
Additional return from wvdial includes primary and secondary DNS
addresses, and some garbled characters, and does appear to exit
gracefully after ^c. ifconfig does indicate an active interface at ppp0
at the same IP address that the wvdial reports. The connection does not
work to retrieve web pages with Firefox. More primitive command line
connection tests have not yet been attempted.

I found a page here which is unfortunately too arcane for me to get much
value from.

http://www.mjmwired.net/kernel/Documentation/usb/acm.txt

The immediate obstacle I find is here:
++++++++++++++
To use the modems you need these modules loaded:
57
58 usbcore.ko
59 uhci-hcd.ko ohci-hcd.ko or ehci-hcd.ko
60 cdc-acm.ko
61
62 After that, the modem[s] should be accessible. You should be
able to use
63 minicom, ppp and mgetty with them.
++++++++++++++
I have not found these modules loaded using `lsmod | grep [appropriate]',
and I am not yet knowledgeable enough to correct these deficiencies.
Would could some knowledgeable helper clarify for me what I actually need
to do to get the appropriate modules loaded, please?

There might or may be other issues, but these are the ones I suspect
right now. Help appreciated with thanks.