[quote=Vex]
Nurse Graves In Underworld should be a merchant (that sells medicine)
read the notes on this page (i dont know if you guys already did this, but she dont sell to me in my game)
http://fallout.wikia.com/wiki/Graves
[/quote]
That is not a bug, she was never set up as a merchant in FO3, she has no merchant inventory or anything. Basically, she is set up like any other not merchant NPC in the game.
The game has a lot of dialogue that doesn't match with the actual game.
For example:
The Megaton Water Processing Plant is not a water purifier and Walter still calls it a purifier (if it was a purifier then why is it necessary to use a GECK to make a purifier as the main objective and a life long project of a bunch of genius scientists, why can't Rivet City build a purifier too, why are all the water sources in Megaton still irradiated, why does Megaton need Aqua Pura shipments and why would they get so angry about a shipment delay, etc).
Sticky in Little Lamplight says everyone is kicked out when they turn 18, but everyone else says it is when they turn 16.
Etc. (I don't want to make a giant wall of text with examples )