[hv=d=w&v=n&n=s102hj7543dq10cj983&w=sa54h2d9752c76542&e=sk863hk96dak864cq&s=sqj97haq108dj3cak10]399|300|Scoring: IMP[/hv] West North East South Pass Pass 1♦ X 2♦ 2♥ 3♣ 3♥ Pass Pass 4♦ X Pass 4♥ X Pass Pass Pass No bid was alerted during the auction. Screens were in use, North and East sharing the same side. After the lead of the ♣Q hits the table and declarer sees AK10 of clubs in dummy, she asks East what the 3♣ bid was. East, a beginner, explains that it was a cue-bid. Neither South nor North were alerted to this during the bidding, so they thought it was natural. (And so did West, East is in fact the only person at the table, or at the tournament, who thinks 3♣ is a cue-bid, for it is not among their agreements). North claims that had she known that 3♣ was a cue-bid she would have passed 4♦X, which might go down if declarer plays sloppily. N/S are very good players (World class), E/W have been learning to play for a year. How would you rule?