Whoa! - Since we added a note to the docs that StringIO supports Unicode, we clearly should continue to support that, and it's a bug if it doesn't. - OTOH, Unicode for cStringIO should be considered at best a feature request. I don't mind if cStringIO doesn't support Unicode -- it never has, AFAIK, so it won't break much code. I don't believe it's much faster than StringIO, unless you use the C API (like cPickle does). - Of course, when Unicode is supported, mixing ASCII and Unicode should be supported too. (But not necessarily mixing 8-bit strings containing characters in the range \200-\377, since there's no default encoding for this range.) - Since this changed from 2.1 to 2.2, we should restore this capability in 2.2.1; I would say that 2.2.1 can't go out until this is fixed. --Guido van Rossum (home page: http://www.python.org/~guido/)