AW: why does RAND_add() take "randomness" as a "double"?

[Dr. Matthias St. Pierre]

I think nobody of us needs to be convinced anymore that making it a 'double' 
was a bad idea.
But the RAND api is very ancient and changing the argument type would be a 
breaking change. 
That's why we didn't dare to touch it when we overhauled the RNG implementation 
for 1.1.1,
because we tried very hard not to add unnecessary breaking changes to the ones 
made in 1.1.0.

Matthias