Oil/grease covering outside of outer CV boots

[Multibeemer]

As the title says, I've noticed that both of my 03 4.4i's front outer CV boots are covered with what looks like oil, and there is a lot of grease accumulated at the bottom of the strut support:





The boots themselves look fine - neither one is torn, and the left one was replaced about 20,000 miles ago. The car has just under 96,000 miles on it. At first I thought my struts were leaking, but the stuff that's accumulated along the bottoms of the strut mounts looks way too heavy to have come from the strut, although I suppose it could be oil from the strut that's combined with dirt to form what looks like grease. Any ideas? Thanks.