Callers are using blackmail, and pretending to be at death's door to get on the programme. Yesterday, Avi Goldstar drove all the way from the Golan Heights to present his solution at the Tel Aviv radio studio. But he too was wrong, and the prize money rose again to dollars 17,000 ( pounds 11,200) - breaking all known records.
But this national obsession is not about money. Mr Hamitzer believes he has tapped a goldmine of intellectual energy and competitive spirit. 'Every Israeli thinks he can solve every problem. He is not looking for buried treasure . . . He is doing it because he always thinks he knows the answer better than anyone else.'
This time, for 12 long weeks, they have all been wrong. 'Who is the crazy star who started with the Frenchwoman before she was bought, before the wars, and it all adds up to 238?' Callers have tried everyone from Napoleon to Mr Hamitzer.
Psychologists have been hauled in to ponder Israel's 'riddle mania'. One called it 'pure mental illness'. Another said people liked the distraction from war and politics. Israel Shahak, a leading radical, puts it all down to British influence. 'Riddles have always been an Israeli pastime, ever since the British brought their crosswords in the Mandate days.'
Mr Hamitzer says riddles simply appeal to the Jewish character. 'Everyone in this country thinks they can be a minister. They can rule the world. It is in their history. It is about tackling every kind of situation and seeing how they can get out of it best.'