south facing greenhouse windows

Ok, not sure if anybody can suggest anything here, but it's worth a try.

There's a large greenhouse where I work, used just for plant display purposes (no growing done) Now, two sides are shielded, the roof's opaque, but I've a large North, and south facing area. I'm looking at ways of shielding some of the sun in the south facing window, and i was wondering if there are any climbers/trailers that could be used instead of just using the usual methods of shading.

So, basically, can anybody suggest a decent trailing/climbing plant, ideally that'll grow 2-4M and wont burn to a crisp under south facing glass? I'm not optimistic, but if there is one, I'm sure somebody here will know it.

 

I think I'd try some of the more tropical passion flowers, but as you probably know they would need to be a fair distance from the actual glass, with good ventilation between the foliage and the glass.
If the winter temperatures in the greenhouse are reasonable it would be a good chance to try some of the less common ones.
My favourite is alata, but I've always wanted to get coccinea to flower, or how about racemosa.