It's mentioned in this forum and in the Blog post I mentioned earlier. All product reach the end of their life and new ones are developed to replace them, the fact ZD is eol doesn't stop it from being a good off-line client.
Originally Posted by syanzy
Your earlier comment saying "...please fix...." isn't really much use in these forums, they are Community support forums and not official Zimbra support and people that post here do so voluntarily and in their spare time (even Zimbra staff). If you want to file any bug reports then you should visit bugzilla and do it there, that gets the attention of developers not posts in these forums.