Trying to understand I8N...

Hi, I admit it: I'm not an expert in I8N. However I realize that XWiki being a wiki we need to have strong I8N features so I'm trying to catch up with I8N knowledge... I started yesterday by reading this excellent short tutorial http:// www.joelonsoftware.com/articles/Unicode.html (The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!)). It's very good and an easy read. I recommend it to everyone. This led me to a few questions: 1) Is UTF8 supported on all platforms? Is it supported on mobile platforms for example? 2) I see in our encoding guide on http://www.xwiki.org/xwiki/bin/view/ AdminGuide/Encoding that we need to set the encoding for the container. Why is that required? The servlet container reads pages which have the encoding specified (using Content-Type meta data), so why does it need to be told about the encoding to use? 3) I see that in our standalone installation we use - Dfile.encoding=iso-8859-1. Now that I've read Joel's tutorial it seems to me this is not going to work for everyone and that we should rather use -Dfile.encoding=UTF-8 by default. WDYT? 4) Should we use the platform encoding or default to using UTF-8 all the time? (this question is related to 1)). I think we should use the platform encoding but I'm curious to know what others think. 5) Jackson Wang is proposing in a patch to modify readPackage like this: private Document readPackage(InputStream is) throws IOException, DocumentException { - byte[] data = new byte[4096]; + //UTF-8 characters could cause encoding as continued bytes over 4096 boundary, + // so change byte to char. ---Jackson + char[] data = new char[4096]; + BufferedReader in= new BufferedReader(new InputStreamReader (is)); StringBuffer XmlFile = new StringBuffer(); int Cnt; - while ((Cnt = is.read(data, 0, 4096)) != -1) { + while ((Cnt = in.read(data, 0, 4096)) != -1) { XmlFile.append(new String(data, 0, Cnt)); - } + } return fromXml(XmlFile.toString()); } However with my new understanding I'm not sure this would help as char are stored on 2 bytes in Java and UTF-8 encoding can store on up to 4 bytes. Am I correct? However, I would rather use http://jakarta.apache.org/commons/io/api- release/org/apache/commons/io/IOUtils.html#toString (java.io.InputStream) than code it ourselves... Sounds safer, shorter, less maintenance, etc to me... :) Thanks for your help -Vincent