I fear we're beating this to death. The Charter itself is clear:
Article 33: This Charter shall not be amended save by [vote of] a majority of two-thirds of the total membership of the National Congress of the Palestine Liberation Organization [taken] at a special session convened for that purpose.
This special session has never been called, much less a vote taken. It doesn't matter what Peres, Arafat, or Clinton say. It's never been amended and stands as written. Its as though the mayors of Chicago, LA, New York, and DC got together and repealed the 2nd amendment. Then Clinton, Reno and a dozen assorted governors accepted it. It didnt happen, nothing was amended.
As to why the session hasn't been convened, many think it's to give the PLO's future actions deniability. And a 2/3 vote to accept Israel wasn't achievable in 93 or in 95, certainly not now.
Barak had a white paper HERE prepared listing all of the Palestinian breaches and then had the paper buried because he was scared to expose Arafat as the traitorous liar he is on the rationale that there was nobody else to negotiate with.
I hope that once they do get back to the negotiating table the first order of business will be to table the White Paper and have Arafat (if he's still around) make good on the breaches before Israel makes any further concessions.