I really don't remember anymore, whether I shorted/bridged pins 4 & 5. It depends on the PCB.
Just take a Multimeter to test whether the PCB already has pins 4 & 5 shorted.
If this is the case you don't need to short pins 4 & 5.
Anyways it won't hurt to short circuit pins 4 & 5 :p .
BTW.: This mod also applies to the RB750