[imp] imap_sort: invalid argument?

[Paul Reilly]

When I do a message search on something which I know will return
no results, I'm getting an error raised:

Fatal Error: Invalid Argument

The error appears to be raised by the following imap_sort() on
line 34 of /horde/imp/mailbox.php in the runSearch() function.

//                $results = imap_sort($stream, $prefs->getValue('sortby'),
//                                     $prefs->getValue('sortdir'), SE_UID, $imp['searchquery']);

If I comment it out, the messages are not sorted, but the error goes away.

I'm using PHP 4.3.6 with c-client 2004 built with SSL support.

Any ideas?

Paul