It is about the size of a small kiwi with a hard yellowish redish brown outer shell. The inside could best be described as, well, donkey snot being a big lump of translucid goo with a pile of semi-hard greenish lumps about the size of orange pips.
Although I tend to think of them in less negative terms, it sounds like it might have been a kind of passion fruit. The kind I've had in South America (distinct from the brownish ones that I've seen more commonly) have a reddish outside, and inside they're a little like you describe. You say "semi-hard greenish lumps" - how green? how hard? were they really as small as pips?
The passion fruit I'm thinking of has translucent orange-white or greeny-white bits inside, but they're a bit bigger than orange pips. Hmmm. Maybe I'm way off here.
