RE: Pigeonhole redirect is adding a message-id header when it already exists

We are using sieve filter to redirect incoming mails to an external mailbox (gmail) an we are seeing some forwarded e-mails being rejected by gmail because of duplicate headers.

How are you redirecting, like this[1]? I tested this ages ago. I am mostly testing with own gmail account, so can't imagine this not working. It was an older 2.2 server I was testing this on.

[1] if false # true { redirect :copy "shit@gmail.com"; }