Attempting to play and download voicemails now that I have fop2 running on the right machine.

I can see a list of the vm's when I click on the envelope icons for an extension. At that point I get a screen that show Play and download icons, but neither do anything. I've read enough to recognize the issue as a likely php session issue, and when I invoke download.php directly from the browser, i get "no way".
But, before that, I'm seeing

[Thu Jul 24 14:49:06 2014] [error] [client 96.56.230.76] PHP Notice: Undefined offset: 1 in /var/www/html/fop2/download.php on line 116

in my http error log, which corresponds to this line:

list ($getid,$filename2) = preg_split("/!/",$_REQUEST['file'],2);

Assuming that I've passed the following URL:
...../fop2/download.php?file=/var/spool/asterisk/default/102/INBOX/msg0000.WAV

I'm seeing the entire $_REQUEST['file'] in $getid, and $filename2 is what is undefined. I've been searching far and wide for what the pattern "/!/" represents, the closest thing I've come to is a negative lookahead.

So I wrote a little test program:
$lines = file("test.out");
$foo = array( "","" );

foreach ($lines as $a) {
echo "$a\n";
$foo = preg_split("/!/",$a,2);
echo "$foo[0] ... $foo[1] ..\n";
}
echo "done\n";

And fed it these filenames:

/var/foo/bar/test
foo/bar/test/gooey/
/var/www/html/fop2/foo.bar

and it produced the same result:

/var/foo/bar/test

PHP Notice: Undefined index: 1 in /home/agiletel/test.php on line 8
/var/foo/bar/test
... ..
foo/bar/test/gooey/

PHP Notice: Undefined index: 1 in /home/agiletel/test.php on line 8
foo/bar/test/gooey/
... ..
/var/www/html/fop2/foo.bar

PHP Notice: Undefined index: 1 in /home/agiletel/test.php on line 8
/var/www/html/fop2/foo.bar

done

I'm running php 5.1.6, and there doesn't seem to be any dependence on a particular version of PHP here.

Any thoughts ? I need to get past this so I can get back to grappling with the session issue, which I think is unrelated (and not likely to be solved by this either)

Ron