{use $timestamp}
1. {date_format_timestamp( "Y-m-d", 1147362767 )}
2. {date_format_timestamp( "Y-m-d H:m:i", 1147362767 )}
{var $cur = date_current_timestamp()}
3. {if $cur >= $timestamp} correct {/if}
   {if $timestamp <= date_current_timestamp()} correct {/if}