upgrading the zlib extension to unicode

Hello, So Andrei asked me to upgrade the zlib extension, but I have a few questions I would like to discuss with you: * when receiving an unicode string, what should we do? compress with as-is, prepend a BOM header (and skip it while uncompressing)? (now I'm unsure if PHP/ICU uses utf16 in the machine endianess or not) * when uncompressing, check for a BOM header and return a unicode string if it is present? return always a binary string? I also have another question, but unrelated with the zlib extension, that is what is a binary string in PHP 6? I think there were some changes on that part (and there isn't the IS_BINARY by now) and I don't really now the difference between a binary string and the old string (aka runtime_encode'd string) I hope my questions are clear and make sense, Nuno