I have some code that mounts a remote file system, gets a directory listing, and then unmounts the file system.

After upgraded to php 4.0.3pl1 from php3, the code did not work.  Specifically, I could not unmount the file system.  After looking into this, I discovered that even though I called closedir, the directory was still in use, and therefore could not be unmounted.

This little code segment below shows the problem:
<?
$dh = opendir(".");
closedir($dh);
sleep(30);
?>

During the sleep, which is after the closedir, I did a lsof, and found the following:

apache    444 root    5r   DIR       3,65     1024    47110 /usr/local/www-data/normal/htdocs

To get around this, I put the code which opens, reads, and closes the directory into it's own function.  It appears that when the function completes, the directory is really closed, and I can unmount the file system.

Let me know if you need any more info.