So France did what European Union rules are supposed to forbid. It bailed out Alstom with a generous package of state aid, undercutting the EU's attempt to keep a level playing field for all European companies. The bailout marks the third time in two years Paris has upset the EU by rescuing a French company. In 2001 and 2002, it lent €450 million to ailing computer maker Groupe Bull SA. Last fall, it extended a €9 billion credit line to France Telecom SA, which had racked up one of the world's biggest debt loads.

The trio of rescues is part of a broader pattern of flouting the EU's economic rules. For the second year in a row, France is on track to exceed the union's budget-deficit cap, which is meant to provide a stable economic environment for the euro. France has also resisted opening up its power market even as its state-owned power company, Electricite de France , has expanded across Europe through acquisitions.

France's behavior underscores how the EU , with a combined market second only to America's, is showing strains even as the union pushes ahead with a constitution and prepares to take in 10 new members, from Poland to Malta. The cheating has angered some EU members and could weaken support for the EU's often-painful rules.

"Not only do the French not seem to manage to adhere to the rules, but they don't even seem to try," says William Lelieveldt, a spokesman for Dutch Finance Minister Gerrit Zalm. Mr. Zalm has called on the EU to fine France.