php5-5.3.2 to php52-5.2.13

[n dhert]

A few weeks ago, freebsd switched to php5-5.3.2 instead of php5-5.2.9.
I see there is now also php52-5.2.13 and pgp52-extensions-1.3 in ports/lang
Can one switch back to 5.2.13 when 5.3.2 is already installed and packages
that depend on PHP
are already compiled with php5-5.3.2
I'v never used portdowngrade? How to do it?

But, what if you upgrade other packages that have in their dependencies
php5-5.3.2 ?
Will this not reinstall the 5.3.2. version again, again removing 5.2.x ?