Multiple instances DOES NOT WORK (despite .ini file change)

I searched around a bit and found that to run multiple instances of firefox, the ini file is to be changed (and put in same directory as the portable exe file). I did this with the following line (changed from "=false" to "=true")

AllowMultipleInstances=true

But this still does not work !!!!!

Any help appreciated.

The ini file change was suggested at
https://portableapps.com/node/4295

******* BUT IT DOES NOT WORK *******

Some information :

Version of firefox : 2.0.0.14
OS : Windows XP