A Strange problem calling GetNPCIfCanInteractWith

[klunk]

I have an odd problem, seen both in Anjuta and Eclipse with the C++ dev environment. I am working on the Playerbot code trying to get the bot to talk to a vendor, nothing more than talk at the moment, but when I step thru the code I get strange behaviour, I hit the breakpoint for a call to GetPlayer()->GetNPCIfCanInteractWith(...), step over that and can see that the call returns a non-null value, however when I step over the next line the debugger jumps back to the GetPlayer()->GetNPCIfCanInteractWith(...) line which this time returns NULL. My first thoughts were threading but Eclipse is telling me I am in the same thread for both calls, and I dont understand why it would call the method twice anyway.