cabal-install: Replacing HTTP with HTTPS (was: [PATCH] Bootstrap over HTTPS.)

Turns out cabal-install itself uses HTTP. (Try to grep for “hackage” in the source tree.) Is it due to the HTTP library, which doesn’t support HTTPS (4000.2.12 returns “user error (https not supported)”)? Is there any interest in changing the current state of things? And if so, what is the best way to do it? Would you like to switch to a different library?