[Plugin: Contact Form 7] Tags in 'To' field not working

Hi,

I am trying to use the following in the ‘To’ field:

maillist-subscribe-[your-email-1]=[your-email-2].[your-email-3]@domain.com

Where your-email-1 is e.g. ‘johnsmith’, your-email-2 is e.g. ‘gmail’ and your-email-3 is e.g. ‘com’. This should create the form required by the maillist server:

maillist-subscribe-johnsmith=gmail.com@domain.com

However, it’s not working. The ‘To’ field just comes up as blank on the messages that are sent to my CC address, and the sign-up doesn’t work. Can anyone help?

Thanks!