Problem with LIKE in a SQL function

Hello,
    I have a bit of a problem, I have looked on the archives and didn't manage
to see anything.

I am trying to write the below function

mail_db=# CREATE FUNCTION "user_id_funct_p2"(varchar)
mail_db-# RETURNS setof varchar AS '
mail_db'# SELECT "mailbox" FROM "user" WHERE "mailbox" LIKE (\'$1%\') '
mail_db-# LANGUAGE sql ;
CREATE

mail_db=# select user_id_funct_p2('test');
 user_id_funct_p2
------------------
(0 rows)

If I  do
  SELECT "mailbox" FROM "user" WHERE "mailbox" LIKE ('test%') ;

It does returns the following results

 mailbox
----------
 test0001
 test0002
 test0003
 test0004
 test0005
 test0006
(6 rows)

If I ammed the function to return $1 it does return as test.  When I looked @
the debug output it seemed to be matching $1 rather that the value of $1.
That leads me to believe that my character escape sequence is incorrect.  I
have tried every possible combination but I am still not returning valid
results.

Many thanks in advance

Mole
--
==============
Caroline Fletcher
Head of Systems