Ferrari’s newly launched 2009 single seater, the F60, has been declared “illegal” by a specialist German motoring publication.

Auto Motor und Sport said the car, revealed last week at the Mugello circuit in Italy, features rear exhaust outlets that contravene the sweeping new technical regulations.

The magazine said some of the Italian team’s rivals have noted that because of the new rules cracking down on bodywork appendages like aerodynamic winglets, exposing the exhausts in the way the F60 is designed is not allowed.

A glance at the other new cars revealed so far - the Renault, Williams, McLaren and Toyota - shows that their exhausts have all been mounted in-board.

Auto Motor und Sport said it should not be too much of a problem for Ferrari to redesign the exhaust housing, but it may help to explain the team’s retreat from the Portimao group test this week to Mugello.

Officially, Ferrari decamped to Mugello because of adverse weather forecasts for this week, but the magazine said the F60 also showed a significant problem with its front wing when tested last week.

It is suggested that, in light of these challenges, Ferrari concluded that it should be conducting the car’s first major test as close as possible to its Maranello base.

Following the “difficult” track debut of the F60 on Monday, Ferrari decamped to the engineering transporters on Tuesday to analyse the birth of its new 2009 single seater.

“After such serious rule changes, the shakedown is always a very difficult affair,” Brazilian Felipe Massa, at the wheel of the Mugello debut, said.

“In the next tests there will be changes (to the car),” he revealed.

On Monday, the car - also hosting the circuit debut of a Ferrari KERS system - completed only about 100 kilometres.

Even the Italian marque’s president Luca di Montezemolo was present for the roll-out debrief. According to reports, the most troublesome areas of the F60 was KERS, and also the new front wing.

It is also suggested that the F60 features a radical solution to the new aerodynamic restrictions for 2009 in the area of the underbody.

Ferrari’s aero-detailing of the side mirror mountings is also distinctive, and a subtly different colour of red paint has been used because it is slightly lighter than last year’s tint.

Following the Tuesday debrief, Ferrari chiefs arranged to depart Mugello and prepare for the car’s proper test debut, alongside other teams next week at the Portimao circuit in Portugal’s Algarve region.

“The season is going to be completely unique,” team boss Stefano Domenicali said earlier this week. “We have had to make a great many changes in a very short time, but I hope that from the outset we are competitive.”

Technical director Aldo Costa added: “The car is not an evolution of the F2008. Quite the opposite: we began with a clean sheet of paper and built a completely new car.”

Check out Ferrari F60 video

Most years it’s more of the same. All the constructors in the FIA Formula One World Championship unveil their cars, and for the most part they look the incredibly similar to the ones they had last year. Big whoop. But every so often, the technical regulations are shaken up a little and the cars come out looking entirely different. This is one of those years — say “hello” to the Scuderia Ferrari F60.

The most substantial changes have been made to the aerodynamic formula, which has dictated a bigger front wing and a much narrower rear aerofoila. F1 has also moved back to slick tires, while underneath the more streamlined bodywork Ferrari has fitted the new Kinetic Energy Recovery System (KERS) developed together with Magneti-Marelli, along with the new carbon-encased seven-speed sequential gearbox with limited slip differential.

Ferrari has opted to call this the F60, eschewing the typical numbering system that would have labeled it the F2009 while highlighting the fact that this will be the 60th season of Formula One – in which Ferrari is the only team to have competed in each and every one. Due to weather conditions, the official live unveiling of the F60 was moved from the company’s on-site Fiorano test track to its Mugello circuit, where Felipe Massa will test drive it for the first time.