The Serial interface is used to communicate with the Infoman or InfomanEFM during several update processes (e.g. software, modem firmware, ...).
There is no setup necessary for Windows systems, accessing the serial interface on Windows works out of the box.
On Linux operating systems there are sometimes additional setup procedures necessary. Some
Linux distributions have restrictive settings which do not allow a normal user to access
a serial interface. So to setup the serial interface for Linux you only have to add your
system user to the groups uucp and dialout, that's it.
On Mac OS X operating systems there are sometimes additional setup procedures necessary. Mac OS X has restrictive settings which do not allow a normal user to access a serial interface.
The user must be a member of the group uucp, you have to create the folder
/var/lock and set the ownership to the group uucp for that folder.
If you run into trouble while accessing the serial interface under Mac OS X, delete the files
RXTXcomm.jar and librxtxSerial.jnilib under
/Library/Java/Extensions, these files come automatically with the Apple JavaVM
and can conflict with the built-in files that come with the Infoman Diagnostic Manager.
NOTE: Those files will come back when you update your Java version on your Mac!