German relief that unemployment has hit a six-year low cannot hide growing concerns about the rise of new, insecure jobs and a growing shortage of skilled labour.

The drop in the jobless rate to 8.8 per cent from 9.1 per cent the previous month - leaving 3.6 million Germans out of work - suggests an end to the country's mass unemployment nightmare. But a study by the German Chamber of Industry and Commerce says that one in two industrial companies is unable to fill its open positions.

Anecdotal evidence suggests thousands of unfilled engineering and computer jobs, with even less-skilled workers, such as welders, in high demand.

"Companies in some key industries, like the electrical sector, have started looking for desperately for highly qualified personnel such as engineers," said Andreas Rees at UniCredit in Munich. Siemens has begun to offer "finder's fees" for engineers.

The problem - and the consequences for Germany's resurgent economy - has started a round of ideological bickering among Berlin's grand coalition. Social Democrats (SPD) blame companies for failing to live up to their traditional obligation to take on trainees in the recent slack years.

Christian Democrats (CDU), meanwhile, have raised the prospect of loosening labour regulations to attract skilled foreigners. Several attempts in recent years to do that yielded disappointing results.

A study released by the Organisation for Economic Co-operation and Development (OECD) this week showed that Germany had attracted 13,000 fewer skilled migrants in 2005 compared with a year earlier. At the same time, the OECD's International Migration Outlook shows an accelerating brain drain of skilled German workers to better-paid jobs in the United States, Britain and Italy.

German unions have complained that new job creation is coming at the expense of job security. They point to a growing trend of companies outsourcing employees to low-cost subsidiaries then hiring them back for less money and longer hours.

"The new subsidiary exists only on paper - one hospital reduced its workforce by 80 one year, then 'borrowed' 80 agency staff from its own in-house agency," said a report by services union Verdi, published in the Süddeutsche Zeitung daily.

The practice, widespread in hospitals, airports and the media, comes as a shock in Germany, last bastion of job security.