# Add/Update or delete an address
my %hsh;
my @arr=split /\s*,\s*/, $addresses;
@hsh{@arr}=@arr;
# Add/Update an address
$hsh{'Joe Schmoe joe@schmoe.com'}='Joseph Schmoe joseph@schmoe.com';
# Delete an address
delete $hsh{JoeBob Schmoe joebob@scmoe.com};
$addresses = join ", ", values %hsh;