German newswire reports say that Thomas de Maiziere, the country's interior minister, is asking the nation's politicians to stop using their smartphones in favour of a BSI-certified SiMKo 2 handset.
Dr de Maiziere made a similar call last November, but the Handelsblatt daily newspaper says his main concern centres on the fact that email push services route messages via servers which can be outside Germany and are therefore open to interception.
The BlackBerry smartphone has been singled out for criticism in the German media owing to the fact that, although the email system uses encryption, it is a proprietary technology.
On the ZDNet newswire, Dancho Danchev, a security researcher, says that the SiMKo 2 smartphone - which was unveiled at the CeBIT computer Faire in Hannover last spring - is exclusively marketed to government agencies, and has been recommended by the Federal Office for Information Security (BSI), for handling classified material.
According to Danchev, earlier this year, the French cabinet found an alternative solution, and adopted the TEOREM phone.
As reported by Infosecurity last year, meanwhile, President Obama in the US originally wanted to use his BlackBerry smartphone when he entered office, but Secret Service officials persuaded him to use Sectera handset.