Q: "I know the male side of the Source is clean, but those who were driven mad before, will they be cured?"
RJ: "No. Whatever the degree of taint channelers have won't change. (they won't get more)"

And:
Moridin: "When/if Rand manages to remove the taint placed on saidin, are the people infected with it cured? Or does their condition remain the way it is?"
RJ: "When/if the taint is removed from saidin further ill effects are stopped but what has already occurred remains."

Apparently the madness caused by the taint can only be cured by the TP. RJ said:
"In Prologue to The Eye of the World, we saw Ishamael use the True Power to Heal insanity. The One Power can not be used to Heal insanity."