Statute for MEPs
Until the European elections in 2009, members of the European Parliament were paid by their national governments on the same basis as their colleagues in the national parliaments.
They were also taxed at national level. This has lead to huge pay discrepancies between deputies, which became even greater with the enlargement. An Italian MEP earned about 12.000 Euros per month, whereas a Hungarian MEP only earned about 800 Euros.
In July 2005, the Council agreed to a single statute for all MEPs, following a proposal by the Parliament. It got effect as from 2009 and gives the MEPs an equal salary.
You can see the actual salaries and other benefits under Salaries
The Treaty of Nice introduced a qualified majority vote on the MEP's statute in the Council, see now the Article 223.2 TFEU.
European Parliament adopts a single statute for MEPS: http://www.europarl.europa.eu/oeil/file.jsp?id=5254742
Rules of Procedures of the European Parliament: http://www.europarl.europa.eu/sides/getDoc.do?pubRef=-//EP//TEXT+RULES-EP+20060703+INDEX+DOC+XML+V0//EN&language=EN
MEPs adopt pay and perks reform: http://news.bbc.co.uk/2/hi/europe/4123550.stm (BBC)