[akanevsky]

You could use a plugin with the following code:

PHP Code:

$getposts = $db->query_first("
    SELECT COUNT(*) as count 
    FROM " . TABLE_PREFIX . "post 
    WHERE userid = {$vbulletin->userinfo['userid']} 
    AND (" . TIMENOW . " - dateline) < 432000"
);
$show['something'] = ($getposts['count'] >= 5 ? true : false); 


Where 432000 is the number of seconds in 24 hours, and something can be replaced with anything you want, as long as it's a proper variable name. Which hook you choose depends on where it is to be used. Or, since you are using it in the "how to create your pages" hack, you can just place the code before $navbits = construct_navbits($navbits); in the php code.

And once you add the plugin (or the code into the page), you can use $show['something'] in your template.