No neither, But I make a Leffe clone for my Father using the good old syrups. He loves it and I must addmit its not that bad either. But the last one I made for Him I fermented at 22, to increase the esters and what not, but in turn decreased them.
You could try the "30c rule" that Ed told me about.
Pitch at A and let it rise to B during the Ferment. A + B = 30c.
For example, pitch at 12c and let it rise to 18c.
i've only heard it in relation to wheat but may well work for belgians... I'm sure i've heard something like that for Chimay too. You'd want a little bit more yeast than normal I'd imagine.