trying to debug ssh-askpass problem

[Frederik Eaton]

Hi all,

I have a script which calls ssh-add at a certain point, and I'm
getting the following error:

ssh_askpass: exec(/usr/bin/ssh-askpass): No such file or directory

I don't see why it's doing this, since SSH_ASKPASS isn't set, and
there should be a working terminal:

     SSH_ASKPASS
              If ssh needs a passphrase, it will read the passphrase from the
              current terminal if it was run from a terminal.  If ssh does not
              have a terminal associated with it but DISPLAY and SSH_ASKPASS
              are set, it will execute the program specified by SSH_ASKPASS
              and open an X11 window to read the passphrase.  This is particu-
              larly useful when calling ssh from a .Xsession or related
              script.  (Note that on some machines it may be necessary to
              redirect the input from /dev/null to make this work.)

How can I find out what is causing ssh-add to try to execute
ssh-askpass?

Thanks,

Frederik