serial device

[kidlinux]

I'm using diald to establish a dynamic IP ppp dial-up connection.  I understand in diald.conf I am supposed to set a device.  Is this device supposed to be the same as my modem, or just any unused serial device?  Right now, I have it set at /dev/ttyS5, and that seems to cause problems (as did /dev/ttyS10).  I receive the following errors in /var/log/syslog:

diald[873]: failed to get initial modem terminal attributes: I/O error
diald[873]: could not get initial terminal attributes: I/O error

I think that keeps occuring as long  as I let diald run.  I think the following messages appear when I attempt to dial (and the dialing and connecting occurs, however I am dissconnect shortly after):

pppd[878]: Connect script failed
chat[882]: Can't restore terminal parameters: Invalid argument

The first set of lines I have above then continue until I kill the diald process.  Are my problems simply my mis-selection of a serial device, or what?  I was also wondering if anyone using diald and IP masquerading could give me an example of how they change their routing depending on the status of their dynamic IP ppp dial-up link.
Thanks a lot.
 

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  http://www3.sympatico.ca/mad
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