Here is the fix
In include/class.email.php starting on line 161 (unmodified file numbering)
replace the code:
$headers = array ('From' => $from,
'To' => $to,
'Subject' => $subject,
'Date'=>date('D, d M Y H O'),
'Message-ID' =>'<'.Misc:(6).''.time().'-'.$this->getEmail().'>',
'X-Mailer' =>'osTicket v 1.6',
'Content-Type' => 'text/html; charset="UTF-8"'
);
$mime = new Mail_mime();
With:
$crlf = "\n";
$headers = array ('From' => $from,
'To' => $to,
'Subject' => $subject,
'Date'=>date('D, d M Y H O'),
'Message-ID' =>'<'.Misc:(6).''.time().'-'.$this->getEmail().'>',
'X-Mailer' =>'osTicket v 1.6',
'Content-Type' => 'text/html; charset="UTF-8"'
);
$mime = new Mail_mime($crlf);
Really easy but this drove me crazy!