Thank you BrowserUk. Actually, #2 was the problem. I got around with following code. Also, I got rid of GD::Graph::Data. My if is closed. BTW, I am new to perlmonks and am very happy to see quick response on the site. 
my @data = (\@log_date, \@deimos_open_bugs);
my $myimage = $mygraph->plot(\@data) or die $mygraph->error;

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In reply to Re^2: Having problem graphing with Perl GD module by rakheek
in thread Having problem graphing with Perl GD module by rakheek

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