In article , Philippe Gautier Philippe.
writes

From another gardening group. Solanum quitoense or Naranjilla.
Apparently edible fruit (Don't if I would dare, given the Datura
resemblance).

here is a pictu pretty convincing match (especially the thorns on the
leaves):

http://tomclothier.hort.net/album/photo/quitoens.jpg

http://vtgcrec.ifas.ufl.edu/pages/Se...03-plant2a.JPG

Your leaves seem to me a little shinier - these seem a bit matte. But it
does sound the most likely option - please post again and confirm the
diagnosis once they've flowered!
--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/edward/index.htm