Hello Perl Monks. Thanks for the help yesterday solving my issue. I implemented Cristoforo's solution and it worked like a charm. However, as I have time, I will work the other solutions into my code; I'm learning a lot from everyone here and I greatly appreciate your assistance. Thanks again and I hope to contribute to the knowledge base in the near future.

BTW, the entire script processes three hash tables, each with between 14 million and 28 million k/v pairs and outputs a forth hash table in the same size realm in about 20 minutes. Perl Monks rock!