First off, I thought telnet was strictly TCP and that anything serial would have to be PPP.
What were you going to script with CL telnet if you could get it to work serially? If it involves any sort of SendKeys or AutoIT, it is doomed to fail.
BTDTGTTS

As I mentioned, I use HyperTerminal with KiX and AutoIT to automate pulling data from network switches, albeit with TCPIP telnet, nothing serial.
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