BRUSSELS, Belgium - After a smooth holiday debut, Europe's new single currency was put to the test Wednesday as stores reopened and people headed back to work with unfamiliar money in their pockets.
Despite some shortages of new euro cash among stores and customers alike, fears of mile-long queues and angry scenes at cash registers appeared to be unfounded, at least during the morning rush.
Shopkeepers reported the majority of customers were still unloading their old, national currencies.
"Most people are paying in German marks, but ... it's only the first day," said Mehmed Tasar, serving croissants and sandwiches to morning commuters in Frankfurt. "In another week there won't be any German marks here any more."
In central Rome, customers were paying in lire only at a pharmacy on Via Gambero, forcing the staff to convert back from euro prices.
"It's a bit chaotic," said pharmacist Roberta Panocchi, as she punched in the euro price for a tube of toothpaste into the register, then figured out the lira price for her customer, Valentina Monaco.
"These are the first days," Monaco said apologetically. "We're not used to it."
The euro, a decade in the works, became legal tender with the dawning of the new year. It is perhaps the most concrete evidence of Europe's transition from a divided continent to a team of nations working toward the same goals.
The 12 European Union nations that adopted the euro are parting with currencies that have long histories -- such as Greece's drachma, which stretches back 2,600 years.
National currencies will circulate side by side with the euro for up to two months to help ease the transition, but European Central Bank officials are hoping that most people will use only euros after the first two weeks.
The foot soldiers in the switch will be Europe's retailers, who are expected to take in the old and hand out the new in change to help remove national currencies from circulation.
But that wasn't happening everywhere.
"My problem is I don't have enough bills," said Mourad Mahoudi, who runs a grocery near the European Union headquarters in Brussels.
When people come in with 50 euro notes (worth about $44.50), he is forced to hand out change in Belgian francs, going against the whole spirit of the operation. "But I hope to get to the bank later in the day," he said.
At one Madrid cinema, the cashier insisted on paying back change in pesetas, explaining she was trying to get rid of the old coins too.
Complicating matters in France, five main banking unions began a one-day strike Wednesday to demand higher pay, more hiring and better security.
But French Finance Minister Laurent Fabius said participation in the strike was "very limited," with almost all workers on the job at three of France's major banks. Bank of France governor Jean-Claude Trichet said that overall, the country's switch to the new currency has "gone over very well."
"We need a euro that inspires confidence and I think we have achieved that," Trichet said.
Two of the six Bank of Italy unions also walked out in an attempt to force mediation of a contract dispute. However, bank officials said branches in major cities would remain open.
Europeans flocked to automated teller machines throughout the day on New Year's -- their first chance to get their hands on the multicolored euro notes.
Italy's Banca di Roma reported record ATM action -- 21,000 withdrawals by late afternoon, totaling 3.5 million euros ($3.1 million). In Belgium, more withdrawals were logged by 8 a.m. than in the entire day a year ago.
The European Union's executive Commission called the first day of the currency switch a success, saying no major glitches were reported from any of the 12 euro-using nations. But the real test was Wednesday, the first day of business following the holiday.
Italian Economy Minister Giulio Tremonti warned shoppers to be attentive to the conversions to prevent "clever" salespeople from rounding up the prices unfairly.
In Rome, Giuseppine Camerotto, a 54-year-old housewife from northern Veneto, was well-prepared with a calculator and a special changepurse with little euros printed on it.
But she still was using lire only, saying she didn't feel comfortable switching over to the new currency while she was away from her hometown.
"I'm a tourist now and I'll continue being a tourist for the next three days," she said.