Hi elfi!
At first glance I thought it was a Nicotiana ( flowering tobacco)but now I am not sure.

You could use this info as a starting mark as you check it out on the web.
Please let us know your findings.

Thanks Marleneann!
I had a look at this Nicotiana but this seems to be a lower plant where those purple bells in my picture come from a shrub and the flowers don't seem to have this little skirt around them, although on one of the flower in my picture there is a small edge/skirt, it nearly looks like on the others, it's been eaten off.
Let's hope someone else comes up with a better option and I'll keep looking myself too and keep you up to date.

Is it Ichroma (sp)

Kiwi I think you are correct. Well done.
Here is a pic
http://www.cottagefarmsdirect.com/search.aspx?UserID=1492812&SessionID=x8CCjxbZ4pUaHhdDUzG4&keywords=Ichroma%20

Thanks kindly Kiwi and Marleneann for your help and for the link to cottagefarms too.
Elfi