Forward mail to multiple recipients with exim4

I use a server to forward email sent to various domains to the appropriate users' main inboxes. I've got a fairly standard exim installation with the following major change to the configuration:

domainlist local_domains = lsearch;/etc/virtual/domains.list

sender_redirect:
    driver = redirect
    domains = lsearch;/etc/virtual/domains.list
    data = ${lookup{$local_part}lsearch{/etc/virtual/domains/$domain}}

catchall_redirect:
    driver = redirect
    domains = lsearch;/etc/virtual/domains.list
    data = ${lookup{postmaster}lsearch{/etc/virtual/domains/$domain}}

The file /etc/virtual/domains.list contains a list of all the domains my server handles mail for, and /etc/virtual/domains/ contains files names according to the domain they pertain to, like /etc/virtual/domains/example.com. Each of those files is formatted like so:

postmaster: me@gmail.com
someuser: address@yahoo.com
otheruser: kittens@aol.com

…and so on. This configuration works as intended. If the user is found in /etc/virtual/domains/example.com, mail is forwarded to the address given, otherwise it defaults to the "postmaster" address as a catch-all.

I'd like to be able to specify multiple destination addresses so that, for example, mail sent to postmaster@example.com would be forwarded to both me@gmail.com and kittens@aol.com. I tried using a comma-separated list and listing the user twice with different addresses, and in both cases it only forwarded to the first address.

Does lsearch provide a way to do something like this already? If not, is there a way I could modify my configuration to allow it? Any help would be much appreciated.