Mail sending problems

After you have correct php.ini in a virtualserver (setting sendmail -t) the mail for that server started to work.
But now other domains have same problems:
I have verified if there was a -t option set and for someone is ok for other one I am not able to find php.ini except for the one in /etc/php.ini (should be general one)
Don't know why some virtualservers have its own php.ini and others not (??)
Anyway, even, after an Apache restart, forms in installed CMS still do not send mails (i.e. new registrations or contact forms and so on)
And other domains do not receive ...
What can be ?

Notes:
- Of course I have re-checked dns configuration on domain registrations forms and they are ok.
- I have just put same ip (of server i have VM on) for mail. smtp. ftp. www. etc...
- Some domains were working fine and now not ... it's a strange thing cause i have just doen normal and safe installing script or automatic updates.
Everything with VM control panel.

Status: 
Closed (fixed)