There is a easy way to get what would be in the x-original-to tag?

[EthraZa]

If someone send a message to bcc, the To tag in the mail header will be

To: undisclosed-recipients:;

Some SMTP server have the ability to add a X-Origitanal-To or X-GM-Original-To (Gmail) header tag with the destination email address, but it's not the case I'm facing right now, unfortunately. The MS Exchange Online server is just not capable of simple things like that.

So, my question is, do php-imap server have some magic function to get from Header the address that would be in the X-Origitanal-To? By probing the Received tags maybe?