Login Redirect..?

Hi all,

Im working on a login script which pretty much does what it says on the tin but having a slight problem when it comes to logging out.

I have this bit of code on all my pages to determine if there is a session or not, what to display and also grabbing the page URL so then I can use it to redirect the user back once logged out.

For arguements sake lets say we are on page "about.php"

about.php

<?php

function curPageURL() {

 $pageURL = 'http';

 $pageURL .= "://";

 if ($_SERVER["SERVER_PORT"] != "80") {

  $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];

 } else {

  $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];

 }

 return $pageURL;

} 

$thisURL= curPageURL();




include ('includes/openDB.php');

if ( isset($_SESSION['username']) ){

?>

		<div id="loginbox">

				<h2>Welcome <?php echo $_SESSION['username'];?> </h2><br />


<form action ="logout.php" enctype="x-www-form-encoded" method="post">	

<input name="url" value="<?php echo $thisURL;?>" type="hidden"/>

<input type="submit" name="Submit" value="Logout"/>

</form>


				<br />

		</div>

<?

}

else{

	?>

			<div id="loginbox">

	  <form method="post" action="LoginDBase.php">

	<table border="0" align="center" cellpadding="2" cellspacing="0">

	<tr>

      <td><b>Username</b></td>

      <td><input name="myusername" type="text" onblur="validateUsername(this.value)" id="myusername" size="10"/></td>

      <td><b>Password</b></td>

      <td><input name="mypassword" type="password" onblur="validatePassword(this.value)" id="mypassword" size="10"/></td>

	  <td><input type="submit" name="Submit" value="Login" /></td>

	</tr>

	<tr>

	  <td> </td>

	  <td id="uMess" colspan="2"></td>

	  <td id="pMess" colspan="2"></td>

	</tr>  


	</table>

</form>

      Forgot your details? <a href="forgot.php"> Click here</a><br />

      Not a user <a href="register.php"> Register here</a>

		</div>


	<?php

	}

?>

I have a $thisURL variable so when logout is clicked they will be redirected to the same page which they logged out from so I pass this value on.

Now on my logout page I have this

logout.php

//clean up magic quotes

if (get_magic_quotes_gpc()) {

   $_POST = stripslashes_array($_POST);

}

// copy POST input to scalars

extract($_POST);


include ('includes/openDB.php');

if ( isset($_SESSION['username']) ){

		

	//Unset the variables stored in session

	unset($_SESSION['username']);


	echo $url;

?>

				<h2 class="title"></h2>

				<div class="entry">		

				You have been logged out.

		        <p align="center"><a href="<?php $url?>">Click here to return back</a></p>

				</div>

<br />

Im extracting the post which is the url variable. When I echo the value of $url it comes up with "about.php" which is correct so I have included it so that the user can click and return back to that page but when it is clicked it goes to logout.php.

Hope I have made it clear what my problem as it does seem quite perplexed.

Any ideas as to why it redirects to logout and not about?