Dear developers, Since the latest xfce4-session-4.9.0-r1 release, /etc/xdg/xfce4/xinitrc is missing the gpg-agent loader (and some other loaders). This can easily noticed when you use enigmail > the password doesn't cache. This can be solved by using the xinitrc for version 4.8.3-r1.
Yes, it was purposely removed: http://git.xfce.org/xfce/xfce4-session/commit/?id=8909f54d68ac2bd567db43002066433f56f4d876 With some related discussion in: https://bugzilla.xfce.org/show_bug.cgi?id=7018 So it seems to be "as designed" or "the way upstream wants it"
Sorry for hastily closing the bug. Lets keep this open for a bit since I got a reply from upstream they want to reintroduce the support for launching it, but they want to do it more clean way it was done before.
From NEWS of xfce4-session-4.9.2 which is now in Portage: 4.9.2 ===== - Restore ssh and gpg agent starting (bug #7018). Closing. Please please next time use http://bugzilla.xfce.org/ too since we are trying to avoid anything distribution specific in Xfce and work very closely with upstream!