Thanks, that does in deed work but it has strayed a somewhat from what I was trying to do which is probably because I tried to simplify too much. I am actually trying to subclass Perl DBI so I need: 
DBIx::MyMod
DBIx::MyMod::db
DBIx::MyMod::st

[download]
The user of DBIx::MyMod does 
use DBIx::MyMod qw(MYMOD_CONSTANT);
# connect in the root
my $h = DBIx::MyMod->connect(x,y, {XXX => MYMOD_CONSTANT});

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I override connect in DBIx::MyMod and other DBI methods in DBIx::MyMod::db and DBIx::MyMod::st. I want to define and export the constants in DBIx::MyMod but still use them in DBIx::MyMod::db. I believe this would be equivalent to your fred.pl and the previous MyMod example doing: 

fred.pl
use MyMod; # assuming all constants in EXPORT

MyMod::db->fred();

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and 
use strict;
use warnings;
package MyMod;
use MyMod::db;

use constant MYMOD_DEFAULT => 1;
use base qw (Exporter);
our @EXPORT = qw(MYMOD_DEFAULT);

1;

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use strict;
use warnings;
package MyMod::db;
use MyMod;
sub fred {
        print "hello" if (MYMOD_DEFAULT);
}
1;

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Do you know if it is possible to make that work?

In reply to Re^4: Can't import constants in multiple namespaces by mje
in thread Can't import constants in multiple namespaces by mje

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