I had a similar incident with my X5 3.0d, took it to the dealer today. they suspected it was the faulty PCV that caused the oil leaked.

will keep you posted.

__________________
'07 X5 3.0d - Black Sapphire Metallic / Camel interior
Specs: Sport pack, Executive, 7 Seats, OEM 336, Hifi
Mods: Aero Kits, Titanium grilles, 4.8i exhaust, Tinted, ///M Footrest, OEM Sport pedals, OEM Rubber mats, OEM Sunshades, LCI Taillights