Ok I found the solution and for me is quite different to all discussion posted here.
The solution is not download Ca Boundle and upload into openssl folder but as I Am using already an SSL certificate just add this line in the PHP 5.6 php.ini
[openssl]
openssl.cafile= /path/to/your/.ca-bundle
where "/path/to/your/.ca-bundle" is your patch to your ca-bundle file.
All is working now with PHP 5.6