i have made a different php version on a plesk 12 server:
http://kb.sp.parallels.com/de/114753

PHP 5.3 works fine.
PHP 5.2 don´t work, it was the horror, no ssl and many more things, so many libs not working on a new debian 7 with old PHP Version.
The best way is the delivery by plesk default.

yeah, i need it too

Would be good if the additional PHP versions could be used with nginx / php-fpm.
If you tick enable nginx / php-fpm the panel it reverts to the built-in PHP version.

Looks like its almost there already! For instance try this out:
ln -s /usr/local/myphpv/sbin/php-fpm /usr/sbin/php-fpm
Copy the php-fpm.d contents to /usr/local/myphpv/etc

Maybe missing something and would need more investigation 'for the real world' but that appears to be a suitable workaround in some situations.

the 'Multiple PHP Versions' feature is a good thing by the way, but will not get updates on apt by the way. So maybe there can be a way to have 5.3, 5.4 and 5.5 via Plesk by default.

The bigest hint is that a user installed an app like "Moodle" and there came an Update (like to version 2.7) and the install failed in behalf of old php then the installation of the app was broken and the customer very angry (by now).

Very urgent Feature to have a possibility to install / use easy 2-3 PHP Versions for every Domain...better also for every sub-Domain.

next Goal for PHP 12.x or PHP 13 ?

I think this can be rejected - it's not needed as there's already multiple options:

1) Use atomic's PHP Panda! if you don't want to build your own packages/scripts
2) If you want to build your own RPM's (or maintain your own version of atomic, remi, etc. repos, it's easy to add the new PHP handler to Plesk UI with a simple command:

> /usr/local/psa/bin/php_handler --add -displayname <NN> -path <path to php cgi> -phpini <path to php.ini> -type <php handler> -id <NN-custom>

this is covered already via atomic .. install atomic repo and then run
yum install plesk-php-panda

Did you try to use 'Multiple PHP Versions' feature?

http://download1.parallels.net/Plesk/PP11/11.5/Doc/en-US/online/plesk-administrator-guide/72042.htm

It's allow to use any number of different php versions

absolutely a good idea. This is far too complicated to install. And also does not always work.

There should be an easy way to install and use more than one PHP-Version. 5.3 and 5.4 for example.
Thanx

Good idea!