No, that produces From tag like this:
Code:
From: "foobar@yahoo.com" < zimbra@zimbraserver.com >
Its not actually changing the from field. Its just replacing the "Name" part of it to whatever email address. Its not the same as changing identities. The reciever will see that the email is zimbra@zimbraserver.com and the name of that person is foobar@yahoo.com.
I guess you could fool the user into thinking it came from yahoo. Since they will see that email address and so when they press reply they will send it to the yahoo email. But when they try to whitelist or something, they won't actually know to whitelist zimbra@zimbraserver.com