EPOCH TIMESTAMP Conversion Problem

hi all,
   I have a table 'myTable'.   There is an attribute  in the table as,


Column      |            Type             | Modifiers
-----------------+-----------------------------+-----------mydate     | timestamp without time zone | not null


I want to convert MAX(mydate) from myTable to Epoch.


SELECT EXTRACT(EPOCH FROM TIMESTAMP WITHOUT TIME ZONE '2007-11-01
17:42:01.81693') ::int4;


How the above query can be used to convert MAX(mydate) to EPoch value?
Is there any other query that I can use?
I think it is not worth to write a function/procedure to just replace
the value in a query?
    Please HELP...................

Thanks in advance


-- 
Amitanand N. Chikorde.
Software Engineer
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