Outer join

Hi,
I'm using postgresql 7.3.4 on debian. I get bad results
from a two-table left outer join.

First table: select * from descriptions;
   desc_id | description  ---------+-------------    909097 | cap    107890 | resis    223940 | ic    447652 | electro
(4rows)
 


Second table: select * from parts;
   part_id | desc_id | mounting | man_id  ---------+---------+----------+--------         2 |  107890 | SMD      |
7        1 |  909097 | LEADED   |      1         3 |  223940 | LEADED   |      8  (3 rows)
 


Join:
SELECT parts.*, d.description, d.desc_id FROM parts p LEFT OUTER JOIN 
descriptions d ON p.desc_id=d.desc_id;
  NOTICE:  Adding missing FROM-clause entry for table "parts"
   part_id | desc_id | mounting | man_id | description | desc_id
---------+---------+----------+--------+-------------+---------        2 |  107890 | SMD      |      7 | resis       |
107890        1 |  909097 | LEADED   |      1 | resis       |  107890         3 |  223940 | LEADED   |      8 | resis
   |  107890         2 |  107890 | SMD      |      7 | ic          |  223940         1 |  909097 | LEADED   |      1 |
ic         |  223940         3 |  223940 | LEADED   |      8 | ic          |  223940         2 |  107890 | SMD      |
  7 | cap         |  909097         1 |  909097 | LEADED   |      1 | cap         |  909097         3 |  223940 |
LEADED  |      8 | cap         |  909097  (9 rows)                /\                                          /\
       ||                                          ||              p.desc_id
d.desc_id

I don't see why there are rows with p.desc_id and d.desc_id different.
(I learnt sql last week)