I sure looks like one to me.
Apparently the yellow sap in the skin should have a distinct smell (not a nice one) but the inner gel shouldn't smell.
And I also read somewhere that its a laxative if eaten.
So my advice.... cut it, smell it, eat it and it you feel like throwing up and need to go to the toilet pronto, then you've probably got the real deal! Congrats!
(tongue in cheek of course)
Thanks chaps, yer when I broke the leaf it had that slimy gel on the inside. As for the laxative properties I believe it is the latex in the skin that does that?
It has good properties in soothing sore skin, like after sunburn and stings. It has a natural anti-inflammatory effect and is why it is included in some creams (but no where near as good as the real thing).
It's the crusty effect after it dries that can be a little disconcerting, though.