I assumed you can find your way around the BrightBox
Login to your BrightBox, then:
Advanced Settings / Accept/ NAT/ Port Forwarding
Then associate the ports you want.
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC