Well, maybe GD is installed in your home directory. In that case, I guess the simplest way would be to add the following at the beginning of your script (though still underneath the #! line):

BEGIN {
   unshift @INC, 
           '/home/nagesh/progs/lib/perl5/i686-linux',
           '/home/nagesh/progs/lib/perl5/';
}
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Putting it in a BEGIN is important because otherwise it won't have any affect when you say use GD a few lines later. See perlmod for all the details. But, this makes it especially important that the files in your home directory are readable by Perl, which is not running under your user but rather as the Apache account.