okay, i know you said the question was unix in nature and not perl, but since this is perl site, i am going to offer you a perl answer.

you can use the Mail::Sender module to easily send attachments. Below is an example of such:

 ref ($sender = new Mail::Sender({
      from => 'you@abc.com',
      smtp => 'smtp.server.com'}
      )) or die "$Mail::Sender::Error\n";
 (ref ($sender->MailFile({
       to =>'recipient@xyc.com',
       subject => "Here is the file",
       msg => "Attached is your file",
       file => "$filename"
      }))
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