It was a volatile day for European shares on Wednesday. They ended the session slightly up, but with London down due to pessimism about the UK economy. Mining companies were the big gainers, led by Rio Tinto which jumped after announcing job cuts, but drugmakers were weaker, after the European Commission offered concessions to companies reselling prescription drugs.The news that the White House and Democratic leaders in Congress had reached an agreement on a bailout for US car makers benefited their European counterparts. On the foreign exchange front, the British pound fell to its lowest level ever against the euro. It is also weak compared with other major currencies on increased expectations of further Bank of England interest rate cuts. The dollar slipped to a two-week low against the euro.