That is not an error, but rather a notice.
It means that in the $_POST array, there is no index of recruitingservices or practiceopportunities.
Try putting this in:
PHP Code:
print "<pre>";
print_r($_POST);
print "</pre>";
That will print out the $_POST array.
Additionally, you can do the following to "surpress" that error.
PHP Code:
if (isset($_POST["recruitingservices"])) $Message .= "Interest: " . $_POST["recruitingservices"] . "\n";
if (isset($_POST["practiceopportunities"])) $Message .= "Interest: " . $_POST["practiceopportunities"] . "\n";