Need help with Mepis 3.4.3 and Dial-up, please.

I have been using Mepis 3.3.2 for about 6 months now.

This is the ONLY version of Linux that I have tried (and I've tried MANY) that will let me get online with a dial-up modem.

A few days ago I got the new 3.4.3 but it will NOT connect with my dial-up modem.

This is the same computer, same modem, etc., etc. but the /dev/modem
that I have been using returns the message, ???Please make sure you have setup your modem device properly and/or adjust the location of the modem device on the modem tab of the setup dialog.???

When I try 'modem0', 'modem1', 'modem2', 'modem3', I get the same message.

I also have tried '/dev/ttyS0 ', S1, S2, S3 and it finds my modem but says it is 'busy'.

My modem is SmartLink, PCI.

BTW, I have tried 3.3.2 on at least 3 other computers, using the same model of SmartLink modem and it always works perfectly.

I would really appreciate it if someone would be good enough to explain what I need to do in order to use 3.4.3 with my current modem.

Thanks.

Lewis.

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