The bottom 3 inches of the main stem has gone from round and green (like the rest of it) to flat, hard and white-ish. I gave it a prod (very technical) and there was no soggyness. The rest of the plant looks very chirpy, bearing flowers/miniture fruit (one of which has gone blotchy, but the others are stonking).
I really need to get myself a pests & diseases hand book with pictures!