[visited 8/1/12] Without a GPS and with blanket mist, I found this by educated luck, basically heading downhill in the right direction from the main barrow. Its a fairly small enclosure, presumably designed to keep cattle penned in as the high land immediately next to it would have made defensive use very difficult. The banks that are left look to be in good condition, though I didn't walk the whole thing as I was getting rushed for time by this point.
The SMR has this listed as "A Late Bronze Age or Early Iron Age palisaded hilltop enclosure lying on a gently sloping shelf to the south of the summit of Eldon Hill. The enclosure forms an irregular 'D' shape and is defined by a clearly visible stony bank."
I'd go for stock enclosure as opposed to habitation purely because this site is undefendable being abutted by higher ground to the North.