Error Message On All Screens....

I have just installed the script and keep seeing this : Strict Standards: Declaration of smtp_message_class::SendMessageBody() should be compatible with email_message_class::SendMessageBody(&$data) in xxxxxx/public_html/help/mail/smtp_message.php on line 594. Can someone please tell me how to fix this.. I am doing this for a non-profit for free and getting a little peeeeeeved at this message and can't seem to make it go away.. Thank you in advance.