Set up Bluetooth (rfcomm) as a virtual serial port (dev/tty0)

I have a bluetooth device that is discoverable through the command "hcitool scan". Its protocol discriptor is "RFCOMM". I can bind the device to the port rfcomm0 through the command

sudo rfcomm bind dev/rfcomm0 PORT NUMBER 1  

However, the program I am interfacing with requires that the port the bluetooth is connected to is dev/ttyUSB0. How can I bind my device to the port dev/ttyUSB0 or rename dev/rfcomm0 to dev/ttyUSB0.

I can't change the program requirements for the program I am interfacing with - so my bluetooth device has to be bound to the dev/ttyUSB0 port.

Also, my device cannot enter a PIN number - it is a simple EMG and all I can do with it is turn it on and off, there is no way to interface with it.

It is simple to bind rfcomm0 to ttyUSB0. The command is

sudo ln -s  /dev/rfcomm0 /dev/ttyUSB0

But it is advisible to not to use ttyUSB0 as it was commonly used, you can go with some generic names like ttyS99.