[pmwiki-users] the ubiquitous "Cannot modify header information" msg

[Ilana Kingsley]

I've read many of the postings regaring this error msg and can't seem to 
get the msg to go away.

Warning: array_merge() [function.array-merge]: Argument #1 is not an array 
in /opt/apache/htdocs/cswiki/pmwiki.php on line 1290

Warning: Cannot modify header information - headers already sent by 
(output started at /opt/apache/htdocs/cswiki/pmwiki.php:1290) in 
/opt/apache/htdocs/cswiki/pmwiki.php on line 714

I'm running PHP 5.0.4 (cli) (built: May 17 2005 17:25:04)
Install of pmwiki-2.1.beta6

My .php files don't have extraneous ending lines/spaces.

Line 1290 of pmwiki.php is
$AuthList = array_merge($Authlist, (array)@$_SESSION['authlist']);

Line 714 or pmwiki.php is
foreach($HTTPHeaders as $h) (@$sent++) ? @header($h) : header($h);


Ideas?
TIA

Ilana