I use address delimiters to make up addresses to give to companies so I can track how the address gets used (or if it gets sold to a spam agent, etc.) This has worked out great, and to help things along, I've been using Thunderbird + the Virtual Identities add-on.
What this allows me to do is reply to a message with the same email that was used to receive it. i.e. - if an email is sent to firstname.lastname@example.org, I want to reply to the email such that my From/Reply-To header is set to email@example.com, not my default identity.
I don't, however, want to create a new identity for each and every address I use, because they're not permanent, and it's a huge pain due to the sheer number of them (it's easy to make one up... takes way too long to have to setup an identity for each, and I'd have like a hundred identities)
Is this something that can be done with a Zimlet? Or am I stuck having to file an RFE to get this in Zimbra? I'd like to move away from having to use a local client, but this is a pretty major stumbling block for me.
The other option is a zimlet that allows me to edit the from/reply-to header to whatever I want (assuming the option is set in the admin panel)