Apostrophe Problem

Hi, I've developed a site where teachers can upload documents for students to view. Works great, except one teacher with an apostrophe in his name said that when he uploads, he gets an error that says " You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Souza', 'Pat', 'O'Leary', '1')' at line 1" The form is at [login to view URL] and it is processed at [login to view URL] I tried to alter the [login to view URL] file to make changes including a mysql_real_escape string such as: $lastname = mysql_real_escape_string ($_SESSION['member_lastname']); ...but this did not seem to work. I've also had problems in the past with documents with apostrophe's in their name not uploading. Eg: "Introduction_to_rock'n'[login to view URL]". I need someone to rectify the changes in [login to view URL] and let me know what I'm doing wrong. Thanks, Dave