ssh-add automagically started

[Volker Kindermann <openbsd_(_at_)_secspace_(_dot_)_de>]

Hi,

I just discovered a great (little) feature of OpenBSD. I'm running it
on a notebook (together with FreeBSD) and I'm starting the X-Server via
xdm (BTW, very nice login-graphic). 
If I start the window-manager (fluxbox) as an option to ssh-agent and
if I have a keypair in ~/.ssh/ it magically starts ssh-add after
logging in. This is great but I didn't found out how to replicate this
great feature on other OS (resp. FreeBSD)?

Any hints would be fine.

 -volker

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