timespan casting

hi,

thought this up while playing with time spans..

here is my table and data..

bignose=> \d foo
Table "foo"
Attribute | Type | Modifier
-----------+-----------+----------
start | timestamp |
stop | timestamp |

bignose=> select start,stop, stop-start as start_stop from foo;
start | stop | start_stop
------------------------+------------------------+------------
2000-06-22 20:37:12-03 | 2000-06-22 20:37:12-03 | 00:000
2000-06-22 20:40:40-03 | 2000-06-23 20:40:40-03 | 1 00:00
2000-06-22 20:40:53-03 | 2000-09-30 20:40:53-03 | 100 00:00
2000-06-22 20:41:08-03 | 2000-06-23 02:41:08-03 | 06:00
2000-06-22 20:41:30-03 | 2010-11-22 19:41:30-04 | 3805 00:00
(5 rows)

now my question.. first of all is the first start_stop result a little
off ? (talking about the 3 0's..)

second is there a way i can do a select so it says something more human
usable ie : 100 days 22 hours 32 minutes..

jeff