Step 1: Purchase a 2nd copy of FFXI.
Step 2: Register a new POL ID using the codes provided with the software.
Step 3: Create a (Full priced because it's a different POL ID) Content ID.
Step 4: Create any new characters on that ID.
Step 5: Go to FFXI.ARCHBELL.COM and download, install and setup "Windower".
Step 6: Run your first instance of FFXI, log in, and start the game.
Step 7: Minimize, or alt-tab, or do what you must to be able to run another program (i don't have this problem as I have 2 monitors)
Step 8: Run the windowed FFXI shortcut a 2nd time, which will create a new instance of the program, allowing you to have 2 FFXI's running at once.
{Congratulations!} you can now go PL yourself to your hearts content.
Disclaimer: Using any 3rd party apps to effect the function of FFXI or POL is a violation of the terms of service.