Yes, I made no assumtions about the device, just brought up the possiblity. I come from a hardware backround so when I come across something like this and don't want to or can't understand the software/hardware relationship or the data sheet's explantation, I just try and see if I can write a simple testing program to see if I can break the function or not, but that's just me. I tend to trust what I can see on a scope. LOLIn this case I assumed that we were talking about a Pic and in the case of RB3 the diagram is clear on the way the module overrides the I/O function.
Edit, your point with regard to possible hardware and software bugs is valid but I don't believe it to be a problem in this case.