The email address on slide 15 needs fixing. Rather embarrassing to have an obviously mishandling international email address on a slide about how it should be done. There's much too much prose about IDNA2003. Not using it is good advice, but going on for three slides about how to use it is bad. And it could include advice on how to test whether it is in fact used by third-party code in a .jar somewhere. There's too LITTLE prose about doing stuff correctly, I skimmed though some bits, noticed factual errors on two pages, and stopped after slide 84. Tell the author to test how to send mail via javamail, please, he's close but he needs to set another property correctly, or check that it is set. The Javamail docuemntation has the name, something to do with utf8, smtputf8 or eai. There are no usable example programs, which is very strange considering that this is trasining for programmers. One usually makes a github repo or similar. Might want to include that. I get the impression that this is written by someone who has not written any EAI-relevant software in Java, and not tested. Is that correct? Arnt