multiple function launching when URL has more than 2 segments (!!!)

[eluser]dmz[/eluser]
hi guys, anyone can tell me why CI is acting wrong, when in url recives more than 2 segments?

part of: controllername.php -sample function

Code:

function xyz(){
     $this->load->view('header');
     $this->load->view('footer');
mail('[email protected]',"",""); //debugging purpose
}

URL: www.somwhere.com/controllername/xyz/anything


when CI gets this url is fireing the xyz() function 6 times.

without the 3rd segment (in this case "/anything") works as expected.

so what is going on there?
i need to pass one variable to my function to store in db, but it is impossible when the function is fired so many times (6 records in db, 6 emails)

regards