Ah, sorry, submitted wrong patch against 3.2, disregard. Here's the 'proper' version (the functionality isn't changed, just the former patch had an unused and-Falsed out clause for reading environb, which in the end I decided not to use as the surrogateescape approach already covers it just as well for values).

@Éric: yes. Actually the whole patch is pretty much new functionality, which should not be considered for a 2.7.x bugfix release. I've submitted a patch against 2.7 for completeness and for the use of a separately-maintained post-2.7 wsgiref, but unless there is ever a Python 2.8 it should never hit stdlib.

The status quo wrt Unicode in environ is broken and inconsistent, which an accepted PEP 3333 would finally clear up. But there may be webapps deployed that rely on their particular server's current inconsistent environ, and those shouldn't be broken by a bugfix 2.7 or 3.1 release.