Ugh, no it wasn't. Thanks for pointing that out. I can't believe they removed that article - at least it looks like they did, I can't find it on their site now. The Japanese version is still there :-)
The bottom line is: one can't reliably use "println" and "readLine" with sockets due to those methods using the default line ending that is appropriate for the platform the code runs on. Most protocols (HTTP, for example) use "\r\n" for line endings, though.