Importation wtih copy generated some wrong registers..

Hi everyone, I need some help please....

I did some importation from a .csv file to a table

(this is a very small piece of the csv file, but i think its good for
the exemple. the pipe "|" is the delimiter for this file)
001|002|30413000000045027612|002
001|002|30410000000218146611|002
001|002|30406000000664389616|002
001|002|30406000000607799814|002
001|002|30406000000664429313|002
001|002|30406000000607767316|002

(and the respective part of the table is)
cod_empresa int4 NOT NULL,
cod_credor int4 NOT NULL,
num_contr varchar(50) NOT NULL,
cod_filial int4 NOT NULL DEFAULT 1

(so, the data on my tables look like this:)
cod_empresa | cod_cliente | num_contr | cod_filial
-------------+-------------+-----------------------+------------
1 | 9386 | 30410000000762732212 | 3
1 | 7383 | 3,04100000007634E+019 | 4
1 | 5750 | 30410000000763546413 | 3
1 | 3584 | 3,04100000007627E+019 | 6

altough the data on the 'num_contr' column is not exatly the same in the
csv file described above, it ilustrates how the data is being stored on
my table. So my question is, why is it storing some exponential numbers
(rows number 2 and 4) instead of a string???? if you look in the
definition of the table above, the column 'num_contr' is a varchar(50)!
So, what is happening?????

Thanks for any help!!!

=====================
Rodrigo Sakai
Analista Programador
rodrigo(at)2bfree(dot)com(dot)br
http://www.2bfree.com.br
Tel: (55) (11) 5083-5577
Fax: (55) (11) 5549-3598
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