[Dovecot] building a simple antispam plugin

Hello,

I'm trying to build another antispam plugin, but some things are a bit unclear.

In backend_handle_mail I put store the signature returned from signature_extract into my antispam_transaction_context. In backend_commit it appears that the signature is empty. (It wasn't in backend_handle_mail).

Somehow between backend_handle_mail en backend_commit it has been cleared... When I use i_strdup it appears to work. Anyone can tell me where this clearing happens? Is i_strdup the right way to do it then?

Thanks, Alexander