Hardware and performance

[Mon Sep 25 18:25:01 2006] [error] [client 127.0.0.1] PHP Fatal error: Call to undefined function isadmin() in /usr/share/moodle/admin/cron.php on line 31

I don't know what to do to resolve this error exactly. I don't think cron is able to run automatically as a result of this error. I've read through as much as I can but I can't find anything specifically referring to this error.

Any suggestions?

This is cron.php code apparently referred to in the error and the line in question is if (!$alreadyadmin = isadmin()) {

/// The current directory in PHP version 4.3.0 and above isn't necessarily the
/// directory of the script when run from the command line. The require_once()
/// would fail, so we'll have to chdir()

if (!isset($_SERVER['REMOTE_ADDR']) && isset($_SERVER['argv'][0])) {
chdir(dirname($_SERVER['argv'][0]));
}

require_once("../config.php");

if (!$alreadyadmin = isadmin()) {
unset($_SESSION['USER']);
unset($USER);
unset($_SESSION['SESSION']);
unset($SESSION);
$USER = get_admin(); /// Temporarily, to provide environment for this script
}