For some reason, XML 1.0 does not support low level ASCII control characters, even if they are wrapped inside a CDATA section. In my project, there was a requirement to send barcode data in an XML message that contained ASCII charaters from 4-31 and although we wrapped the content in a CDATA section, it didnt help. The parser didnot understand it and blew up. XML 1.1 seems to have added support for control characters, but the parsers we use are yet to offer the support. We resolved the issue by encoding the content to Base64 and asked the downstream apps to decode it back and use it.
Btw, this is my 100th blog entry :)
