Simpel SQL fejl!

$username = $_POST['username'];
$password = $_POST['password'];
$email = $_POST['email'];

$query = "LOCK TABLES users WRITE";
mysql_query($query);

$query = "UPDATE users SET username = '$username' WHERE ID = $_SESSION['ID']";
mysql_query($query);

$query = "UPDATE users SET password = '$password' WHERE ID = '$_SESSION['ID']'";
mysql_query($query);

$query = "UPDATE users SET email = '$email' WHERE ID = '$_SESSION['ID']'";
mysql_query($query);

Fejl i første query:

Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING in /customers/xxx/httpd.www/cms/editprofile.php on line 62

Hvad kan jeg gøre?