(Please CC replies to me, as I'm not on the list.)

Is anyone out there successfully using a Xircom CreditCard (or
RealPort) Modem 56-GlobalACCESS (models CM-56G, RM56G)?  Mine appears
to attach correctly when inserted into my ThinkPad T22 running
1.5.3_ALPHA, as follows:

pcmcia1: CIS info: Xircom, CreditCard Modem 56 - GlobalACCESS, CM-56G, 1.00
pcmcia1: Manufacturer code 0x105, product 0x100a
pcmcia1: function 0: serial port, ccr addr ff80 mask 67
pcmcia1: function 0, config table entry 39: I/O card; irq mask 8ebc;\
  iomask a, iospace 2e8-2ef; mwait_required rdybsy_active io8 io16\
  irqshare irqpulse irqlevel powerdown
pcmcia1: function 0, config table entry 31: I/O card; irq mask 8ebc;\
  iomask a, iospace 3e8-3ef; mwait_required rdybsy_active io8 io16\
  irqshare irqpulse irqlevel powerdown
pcmcia1: function 0, config table entry 23: I/O card; irq mask 8ebc;\
  iomask a, iospace 2f8-2ff; mwait_required rdybsy_active io8 io16\
  irqshare irqpulse irqlevel powerdown
pcmcia1: function 0, config table entry 15: I/O card; irq mask 8ebc;\
  iomask a, iospace 3f8-3ff; mwait_required rdybsy_active io8 io16\
  irqshare irqpulse irqlevel powerdown
pcmcia1: function 0, config table entry 63: I/O card; irq mask 8ebc;\
  iomask 3, iospace 0-7; mwait_required rdybsy_active io8 io16 irqshare\
  irqpulse irqlevel powerdown
com3 at pcmcia1 function 0: serial device
com3: ns16550a, working fifo

However, running tip on tty03 shows that the card is unresponsive;
what's more, the ~. command fails to quit, and the tip process becomes
unkillable.  When tesing with pppd, I found that the modem's status
lights blink once, indicating that some kind of I/O succeeds. But
after pppd times out, unable to send AT commands to tty03, it is
necessary to kill the pppd process manually, which results in the
message "tcsetattr: Interrupted system call".

Any help would be greatly appreciated.

-chris