SMTP error when using mail()

[bobby_rahman]

Hiya Im getting this SMTP error in Win98...has anyone come across it.
Its strange as I know I had email working at some stage.

Warning: mail() [function.mail]: SMTP server response: 451 Temporary local problem - please try later in

This is the code Im trying to run:
function email ($username, $email, $password)
{
$email_add =$email;

$subject = "Bla"; 
$mailcontent =  "Your Username is:	".$username."\n"
		."Your Password is: ".$password."\n";
$fromaddress = "Bla 
\nPlease store this email in a secure place or 
    delete for \nsecurity purposes"; 
mail($email_add, $subject, $mailcontent, $fromaddress);
return true;

}

I have set in my php.ini my smtp server to my ISP account so using
smtp.freeserve.co.uk at moment.

What worries me usually if it cant find the smtp server or the smtp server not working it just times out after 30 secs but this error says there is a local problem.

Thanks in advance who anyone who can point me in the right direction

Bobby