The poster boy of public sector Linux deployment, the City of Munich, has yet again delayed its much publicised roll-out of the open-source OS.

City officials have admitted they have failed to meet their initial deadline of migrating 14,000 PCs running Windows and Office to Linux and OpenOffice by the middle of this year. The migration is now expected to have a year later than planned.

They were quick to deny responsibility however. "A couple of developments have happened since we started this entire process," said Florian Schiessl, a spokesman for the Linux project team. "First of all, the debate on software patents and its impact on users of open source software came in the middle of our public tender process. As a result, we were forced to halt the tender until we could study the situation."

A group of legal experts were commissioned by the city in August 2004 to study the implications of using Linux ahead of proposed European Union legislation. That decision came just two months before Munich had confirmed a final roll-out plan, and over a year since the city first announced its intention to move to Linux.

At the time, the city promised the roll-out would be delayed by only "a few weeks". The experts finally reached the conclusion that there is only a very small risk of software patent infringement, according to Schiessl. "The experts told us that almost every user of software faces some risk," he said.

Then the tender process dragged on - from October 2004 to April of this year - because the offers from the competing bidders "were very different and impossible to compare", Schiessl said. "Some were very comprehensive, others not. So we needed to go back to the bidders and discuss our requirements to achieve greater transparency."

In April, the city finally chose Softcon and Gonicus to install open source software provided through the Debian GNU/Linux project. Since then, IT experts in the City of Munich's migration project, called LiMux, have been working with Softcon and Gonicus on a concept for testing new open source applications in the city's various offices.

"We recently decided to extend the pilot phase another six months," Schiessl said. "We want to make sure that the entire solution works with all of the various services - and not just one piece of it, like Linux."

In November, the LiMux team will begin offline tests of the client software before entering the pilot phase in January, according to Schiessl. In this phase, select staff members will use the new open software client to do their jobs, he said.

Although the City of Munich aims to deploy as much open source software as possible, it has no intention of abolishing Microsoft products altogether, according to Schiessl. "We will continue to use the company's products in areas where it makes more economic sense, for instance, to run department-specific applications on Windows than on Linux. Contrary to what many people have said and written about our decision to use open source software, we have no political mandate against Microsoft."

All of which has somewhat undermined the huge lobbying efforts by Linux advocates who held the Munich roll-out as the prime example of a wider technological revolution.