<?php
  //функция вычисляет разницу между указанной датой и текущим временем
  //результат выводится в формате 57 лет, 7 месяцев, 18 дней, 2 часа, 32 минуты, 49 секунд назад
  //в качестве параметра указывается метка времени UNIX
  function get_date_diff($tmst)
  {    $diff = time() - $tmst;
    if($diff < 0) return false;
    $diff_work = $diff;


    //года, в одном году 365 дней
    $years = 0;
    $seconds_in_year = 31536000;
    $years_capt  = '';
    if($diff_work >= $seconds_in_year)
    {
		    $years = $diff_work / $seconds_in_year;
		    $years = floor($years);
		    $diff_work = $diff_work - $years * $seconds_in_year;

      $years_capt    = 'лет';
      $last_char     = substr($years, -1);
      $last_two_char = substr($years, -2);
      if(in_array($last_char, array('1'))) $years_capt = 'год';
      if(in_array($last_char, array('2', '3', '4'))) $years_capt = 'года';
      if(in_array($last_two_char, array('11', '12', '13', '14'))) $years_capt = 'лет';
    }

    //месяцы
    $months = 0;
    $seconds_in_month = 2592000;
    $months_capt = '';
    if($diff_work >= $seconds_in_month)
    {
		    $months = $diff_work / $seconds_in_month;
		    $months = floor($months);
		    if($months > 0)
		      $diff_work = $diff_work - $months * $seconds_in_month;

		    $months_capt    = 'месяцев';
      $last_char     = substr($months, -1);
      $last_two_char = substr($months, -2);
      if(in_array($last_char, array('1'))) $months_capt = 'месяц';
      if(in_array($last_char, array('2', '3', '4'))) $months_capt = 'месяца';
      if(in_array($last_two_char, array('11', '12', '13', '14'))) $months_capt = 'месяцев';
    }

    //дни
    $days = 0;
    $seconds_in_day = 86400;
    $days_capt = '';
    if($diff_work >= $seconds_in_day)
    {
		    $days = $diff_work / $seconds_in_day;
		    $days = floor($days);
		    if($days > 0)
		      $diff_work = $diff_work - $days * $seconds_in_day;

		    $days_capt    = 'дней';
      $last_char     = substr($days, -1);
      $last_two_char = substr($days, -2);
      if(in_array($last_char, array('1'))) $days_capt = 'день';
      if(in_array($last_char, array('2', '3', '4'))) $days_capt = 'дня';
      if(in_array($last_two_char, array('11', '12', '13', '14'))) $days_capt = 'дней';
    }

    //часы
    $hours = 0;
    $seconds_in_hour = 3600;
    $hours_capt = '';
    if($diff_work >= $seconds_in_hour)
    {
		    $hours = $diff_work / $seconds_in_hour;
      $hours = floor($hours);
		    if($hours > 0)
		      $diff_work = $diff_work - $hours * $seconds_in_hour;

		    $hours_capt    = 'часов';
      $last_char     = substr($hours, -1);
      $last_two_char = substr($hours, -2);
      if(in_array($last_char, array('1'))) $hours_capt = 'час';
      if(in_array($last_char, array('2', '3', '4'))) $hours_capt = 'часа';
      if(in_array($last_two_char, array('11', '12', '13', '14'))) $hours_capt = 'часов';
    }

    //минуты
    $minutes = 0;
    $seconds_in_minute = 60;
    $minutes_capt = '';
    if($diff_work >= $seconds_in_minute)
    {
		    $minutes = $diff_work / $seconds_in_minute;
		    $minutes = floor($minutes);
		    if($minutes > 0)
		      $diff_work = $diff_work - $minutes * $seconds_in_minute;

		    $minutes_capt    = 'минут';
      $last_char     = substr($minutes, -1);
      $last_two_char = substr($minutes, -2);
      if(in_array($last_char, array('1'))) $minutes_capt = 'минута';
      if(in_array($last_char, array('2', '3', '4'))) $minutes_capt = 'минуты';
      if(in_array($last_two_char, array('11', '12', '13', '14'))) $minutes_capt = 'минут';
    }

    //секунды
    $seconds = $diff_work;

    $seconds_capt    = 'секунд';
    $last_char     = substr($seconds, -1);
    $last_two_char = substr($seconds, -2);
    if(in_array($last_char, array('1'))) $seconds_capt = 'секунда';
    if(in_array($last_char, array('2', '3', '4'))) $seconds_capt = 'секунды';
    if(in_array($last_two_char, array('11', '12', '13', '14'))) $seconds_capt = 'секунд';

    //результат
    $arr = array();
    $arr['years']        = $years;
    $arr['years_capt']   = $years_capt;
    $arr['months']       = $months;
    $arr['months_capt']  = $months_capt;
    $arr['days']         = $days;
    $arr['days_capt']    = $days_capt;
    $arr['hours']        = $hours;
    $arr['hours_capt']   = $hours_capt;
    $arr['minutes']      = $minutes;
    $arr['minutes_capt'] = $minutes_capt;
    $arr['seconds']      = $seconds;
    $arr['seconds_capt'] = $seconds_capt;


    $tmp_arr = array();
    if($years) $tmp_arr[]   = "$years $years_capt";
    if($months) $tmp_arr[]  = "$months $months_capt";
    if($days) $tmp_arr[]    = "$days $days_capt";
    if($hours) $tmp_arr[]   = "$hours $hours_capt";
    if($minutes) $tmp_arr[] = "$minutes $minutes_capt";
    if($seconds) $tmp_arr[] = "$seconds $seconds_capt";
    $arr['str'] = join(', ', $tmp_arr);

    return $arr;
  }

  $tmst = strtotime("1954-06-12 12:21:32");
  $arr = get_date_diff($tmst);
  print $arr['str'].' назад';   print "<br />";

  $tmst = strtotime("2012-01-01 09:21:32");
  $arr = get_date_diff($tmst);
  print $arr['str'].' назад';
?>