I read somewhere that this can happen on the 308 when it gets hot, and you park up and leave it. It was a long term test of a Ferrari 308 GTSi Quattrovalvole published in a US magazine called "Inside Line" (Jun 15th 2007)
By breather pipe do you mean the tube that runs from the expansion tank down near the left rear wheel? If so, I have that same issue with mine if I drive for a while. A few drips, nothing significant. Just had a recent major service and assumed that they overfilled it when they replaced the fluid. Hoping it will stop after it has had a chance to equalize. Kind of ironic as all the old oil leaks are now gone!
