@ISA and the paths in 'use libs'

I'm an avid OO perl programmer but it is only recently that I have had
to create modules that would use inheritence. My modules are in a
private area outside of the usual @INC directories so I use the 'use
lib' to point paths to my modules.

The problem I have is that now that I want to use @ISA to inherit a
modules methods, but it doesn't seem to look for it in the 'use lib'
paths I give.

Here are the details:
So in my /home/nj/perl_libs/ I have BaseNJ.pm
In /home/nj/perl_libs/BaseNJ I have a Tools.pm

/home/nj/perl_libs/BaseNJ.pm
---------------------------
#!/usr/bin/perl

package BaseNJ;
use strict;
use warnings;

use lib qw( /home/nj/perl_libs );

our @ISA = qw( BaseNJ::Tools );

[CODE SNIP]

/home/nj/perl_libs/BaseNJ/Tools.pm
---------------------------------
#!/usr/bin/perl

package BaseNJ::Tools;
use strict;
use warnings;

use lib qw( /home/nj/perl_libs );

sub sub_method {
[CODE SNIP]
}

[CODE SNIP]

test.pm
-------
#!/usr/bin/perl

use strict;
use warnings;

use lib qw( /home/nj/perl_libs );

use BaseNJ;

my $obj = new BaseNJ();

$obj->sub_method(); # dies here


OUTPUT
------
Can't locate package BaseNJ::Tools for @BaseNJ::ISA at /home/nj/test.pl
line 9.
Can't locate package BaseNJ::Tools for @BaseNJ::ISA at /home/nj/test.pl
line 13.
Can't locate package BaseNJ::Tools for @BaseNJ::ISA at /home/nj/test.pl
line 13.
Can't locate object method "sub_method" via package "BaseNJ" at
/home/nj/test.pl line 13.



Can someone suggest to me how I could make this work? Or am I doing
something completely wrong? I basically want to split up the methods of
this class into separate files for easier maintenance and read ability.

Thank you all,
Nik J

.