GPG signing of outgoing RT::IR investigations in RT-RT::IR 5.0.8 fails silently over the REST API

Hi,

I have a working GPG agent setup for RT::IR 5.0.8 that works fine once the gpg-agent has been given the correct pass phrase AND the web server has been restarted after that. However, if one forgets to restart the server afterwards, the signing of investigations over the REST API fails silently despite the gpg-agent working fine. And once signing fails, the investigations won’t be sent to the client by email. Is there any way to find this out, return an error code or anything as a response to the REST API call that fails to sign the investigation email?

The RT::IR log (rt5.log) shows lines like

gpg: signing failed: Inappropriate ioctl for device

Br, Mika