In a confidential memorandum, Geunter Verheugen, EU enlargement commissioner, says the Commission should consider suggesting "concrete proposals on dates" for adoption by heads of government in December. The six leading candidates - Poland, Hungary, the Czech Republic, Estonia, Slovenia and Cyprus - aim to complete negotiations next year and to join the EU in 2003. Most EU diplomats consider 2004 more likely and Mr Verheugen said in Prague yesterday that one possibility was for the EU to take in 10 of the 12 countries negotiating entry in 2005. Bulgaria and Romania need longer to prepare. In his six page memorandum, Mr Verheugen points to the problems of winning public support for enlargement