Wrong parameter count for imap_open()

[Adam Williams <awilliam@xxxxxxxxxxxxxxxx>]

I'm running PHP 5.2.4 and getting the error:

*Warning*: Wrong parameter count for imap_open() in 
*/var/www/sites/intra-test/contract/login.php* on line *9

*My code is:

$mbox =
imap_open("\"{mail.mdah.state.ms.us/imap/novalidate-cert:143}INBOX\",
\"".$_POST["username"]."\", \"".$_POST["password"]."\"");   // line 9

but when I echo it out, it looks fine:

echo "\"{mail.mdah.state.ms.us/imap/novalidate-cert:143}INBOX\",
\"".$_POST["username"]."\", \"".$_POST["password"]."\"";

prints:

"{mail.mdah.state.ms.us/imap/novalidate-cert:143}INBOX", "awilliam", 
"xxxxxxx"


any ideas?
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