Answer:
There have been a number of suggestions as to what could be done to alleviate the situation, including:
Immigration: to the South and East of Europe lie considerably poorer countries with young and growing populations. However, immigration is a growing issue in its own right. Also the immigrants themselves will eventually age. Work longer and start receiving your pension later - but are Europeans willing to vote for governments that suggest this?
New birth policies - encourage people to have more children using the tax system perhaps?
The "Policy Plan on Legal Migration" report adopted in September envisages a scheme whereby skilled immigrants are allowed to work and live in the EU. The European Commission has already raised the possibility of a US style "Blue Card" for future skilled workers