Weird behaviour of mail() function

[eluser]verisof[/eluser]
Hi all, I found a very strange thing, hope someone can explain this.

I had a problem with sending email via Email class. It was always ending with FALSE when it came to mail(...) part. So I tried to put my testing simple mail() function to different places.

I used this test code:

Code:

mail("[email protected]","testmessage","testmessage")

1) When I put it to index.php before the first CI code, it worked
2) When I put it to codeigniter/CodeIgniter.php after sending all the output, it worked
3) When I put it to my controller class before the parent::Controller(); call in the constructor, it worked
4)And finally, when I put it anywhere after the parent::Controller(); call (just after it, in some function, anywhere in the Email class it didn't work

(when I say it worked, it means that the email arrived and thu function returned TRUE)

I must add, that I never changed anything "inside" CI or Email class. It seems that right after parent::Controller(); call, the mail() function stops working. I searched my project to find out if I didn't override it by an accident, but nothing like this happened.

I used Email class to send emails succesfully before, but now I can't say what is going on.

Any idea someone?