I know it's been a while since last this thread was updated, but I have this same problem on a new plesk 12 debian server: Xinet stops after auto updates and does not start, the result being that ftp stops working.
For example, today:
The auto updates started ->
/tmp/autoinstaller3.log...
OK, I think I got it. So about the ioncube version shipped in the package php5-ioncube-loader I should blame my hosting provider which set up my server with plesk as well other packages. Thanks!
I think I hit a bug.
New debian wheezy server with Plesk 12.0.18 Update #24 and ioncube:
# php -v
PHP 5.4.35-0+deb7u1 (cli) (built: Nov 18 2014 06:49:05)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies
with the ionCube PHP Loader v4.6.0...