Code:
[+] Compatibility with Parallels Virtuozzo Containers 4.6.
[*] Google Services for Websites localization - now Google Services for Websites can be used in the same language as your current Parallels Plesk Panel locale.
[*] Stability of Postfix queue was increased to avoid the queue file write error.
[-] Virtuozzo promotion in the top frame of Parallels Plesk Panel is removed.
[-] Domains that exceeded limits are not suspended on a server with a lot of domains bug is fixed.
[-] SSL is available for subdomains, but a configuration file for SSL connection is not supported by subdomains bug is fixed.
[-] The size of mail log file is growing and logs are not properly rotated bug is fixed.
[-] Subdomain switching to PHP in FastCGI is applied to consequent subdomains bug is fixed.
[-] Executing statistics tool causes segmentation fault in Postfix when the size of mail log is large bug is fixed.
[-] The Parallels Plesk Panel server does not update traffic of the clients bug is fixed.
[-] The statistics utility generates directories in the wrong format for all domains when invoked after backup restoration or migration bug is fixed.
[-] It takes almost four minutes to open a domain's hosting preferences page bug is fixed.
[-] Problem in libspf which causes incorrect work of SPF rules bug is fixed.
[-] Domain user cannot log in to the server with SFTP, the error 'connection closed' is returned bug is fixed.
[-] Some countries are not listed at the Add SSL Certificate page, so customers cannot generate a CSR bug is fixed.Quelle: http://download1.parallels.com/Plesk/PPP9/rn/en-US/plesk-9.5.3-for-rpm-based-os.html
ACHTUNG: Im Panel wird sogar die 10er Version angezeigt. Das ist mit Sicherheit ein Fehler und sollte nicht installiert werden.