I'm using xDaeMoN's snippet http://www.hawkee.com/snippet/841/
Code:

on *:START: { 
  hmake jcount 100 
  if ($isfile(jcount.dat)) hload jcount jcount.dat 
} 
 
on *:EXIT: hsave -o jcount jcount.dat 
 
on !*:JOIN:#: {
  if ( $hget(jcount,$+($network,.,$chan,.,$nick)) ) {
    tokenize 32 $v1
    var %t = $calc($1 + 1)
    .msg $chan Welcome Back $nick $+ . Last time you joined $chan was on $2 $+ , $duration($calc($ctime - $3)) ago $+ . (Your total visits: %t $+ )
    hadd -m jcount $+($network,.,$chan,.,$nick) %t $asctime(mm/dd/yyyy) $ctime
  }
  else { 
    hinc -m jcount $+($network,.,$chan,.,total.count)
    .msg $chan Welcome $nick $+ ! You're visitor $chr(35) $+ $hget(jcount,$+($network,.,$chan,.,total.count)) to join $chan $+ .
    hadd -m jcount $+($network,.,$chan,.,$nick) 1 $asctime(mm/dd/yyyy) $ctime
  }
}
The output is:

Welcome Back booth. Last time you joined #channelname was on 07/11/2009, 22min 12secs ago. (Your total visits: 6)

I would like it to be:

Welcome Back booth. Last time you joined #channelname was 5 days, 5 hours, 36 minutes, 57 seconds (Your total visits: 6)