Account creation mail subject line in UTF8

When you create a new account in VTiger there is a mail sent out to inform the user of the link, his username and password. This mail, to be nice about it, leaves a bit to be desired. Below you will see a few changes that I made to get the mail to be a bit more informative before the users just trash it.

I changed mine to read:

         $subject = $mod_strings['User Login Details']." für VTiger Planet IC";

I changed to so that UTF8 characters are correctly displayed in the subject line:

        $mail_status = send_mail('Users',$user_emailid,$HELPDESK_SUPPORT_NAME,$HELPDESK_SUPPORT_EMAIL_ID,'=?'.$default_charset.'?B?'.base64_encode($subject).'?=',$email_body);