I did a search through all my third party programs and found nothing (DLTCEP, Infinity Explorer, NearInfinity) that would allow jaheira to detect sw1h50 and interact with the party. The only thing I found with sw1h50 in it was:
IF
Global("D0JahShaz","GLOBAL",4)
GlobalTimerExpired("D0JahShazTimer","GLOBAL")
PartyHasItem("sw1h50")
OR(8)
AreaCheckObject("AR0020",Player1)
AreaCheckObject("AR0300",Player1)
AreaCheckObject("AR0400",Player1)
AreaCheckObject("AR0500",Player1)
AreaCheckObject("AR0700",Player1)
AreaCheckObject("AR0800",Player1)
AreaCheckObject("AR0900",Player1)
AreaCheckObject("AR1000",Player1)
CombatCounter(0)
THEN
RESPONSE #100
SetGlobal("D0JahShaz","GLOBAL",10)
CreateCreatureObjectOffScreen("d0jahrev",Player1,0,0,0)
CreateCreatureObjectOffScreen("d0jahre2",Player1,0,0,0)
CreateCreatureObjectOffScreen("d0jahre2",Player1,0,0,0)
CreateCreatureObjectOffScreen("d0jahre2",Player1,0,0,0)
END
in BALDUR.BCS. There are numerous dialogs I found but I can't find the script that will start Jaheira's initial speech.
Also, I found if you really want to do this quest, you can make sure that the following conditions are met:
Global("D0JaheiraBernardShaz","GLOBAL",0)
InParty("Jaheira")
OR(2)
Global("D0JahShaz","GLOBAL",5)
Global("D0JahShaz","GLOBAL",6)
And then go talk to Bernard. Then you can either give it to him, or keep it.