When you assign to @ISA, you are removing the reference to CGI::Application. Putting a print "@ISA\n" after the use base... line and then after the @ISA=... line shows the problem: 
package Foo;
                                                                      
+          
use base 'CGI::Application';
print "@ISA\n";
use Bar;
@ISA = ("Bar");
print "@ISA\n";

# at this point Foo only inherits from Bar

__END__
CGI::Application
Bar

[download]
Rather than mixing use of use base and directly assigning to @ISA, consider the use of @ISA alone: 
use CGI::Application;
use Bar;
@Foo::ISA = qw(CGI::Application Bar);

[download]
BTW, I believe "bar" should be capitalized in your original code.

--sacked

In reply to Re: CGI::Application and object inheritance by sacked
in thread CGI::Application and object inheritance by spork

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