HTTP_AUTH and SQL WHERE Clause

Hey Folks,
I am having trouble with some variables the $HTTP_AUTH_USER and $HTTP_AUTH_PW - now im useing PHP 4.3.3 and so i know that you have to use $_SERVER['HTTP_AUTH_USER'] and $_SERVER['HTTP_AUTH_PW'] instead of the old way now. Well i am having trouble with this script i have created to authenticate user name and password and verify against a postgresql database below.

$auth = false; // Assume user is not authenticated

if (isset( $_SERVER['PHP_AUTH_USER'] ) && isset($_SERVER['PHP_AUTH_PW'])) {

// Connect to MySQL

pg_pconnect("host=172.18.204.64 port=5432 dbname=acquisuite_db user=pgadmin password=pgadmin") or die ( 'Unable to connect to server.' );

// Select database on MySQL server

// mysql_select_db( 'your_db' )
// or die ( 'Unable to select database.' );

// Formulate the query

$sql = ("SELECT * FROM tbl_authenticate WHERE username = '$PHP_AUTH_USER' AND password = '$PHP_AUTH_PW'");

// Execute the query and put results in $result

$result = pg_exec( $sql )
or die ( 'Unable to execute query.' );

// Get number of rows in $result.

$num = pg_num_rows( $result );

if ( $num != 0 ) {

// A matching row was found - the user is authenticated.

$auth = true;

}

}

The Problem is on the $sql line when i put in the string to do the Query with the WHERE clause having the $HTTP_AUTH_USER and $HTTP_AUTH_PW. When i change it to '$_SERVER['HTTP_AUTH_USER']' and '$_SERVER['HTTP_AUTH_PW']' it does not work and i get a parse error.
How can i get around this?
does anyone have any ideas for me.
Thanks

Cameron Seader
CSeader(at)Idahopower(dot)com

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