Virtual Serial Ports Driver XP 

Using Virtual Serial Ports Driver XP you can create any number of virtual serial ports in your system which will be connected to each other via virtual null-modem cable. You can connect one application to another using virtual serial port pair.
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Share Serial Ports 

Share Serial Ports creates virtual serial ports in your system that appear as copies of real ports and allows you to share real serial ports between multiple applications. All applications will be able to receive and send data to serial port.
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