I figured it out. I am using AAF gem v. 0.4.3 which has a new  
ferret_server wrapper which does not have a non-daemonizing option.  
This patch fixes the problem:
[Patch] Allow ferret_server to run in blocking (non-daemon) mode
http://projects.jkraemer.net/acts_as_ferret/ticket/184
If you are getting a lot of "Throttling respawn: Will start in x  
seconds" messages in your logs, and notice that you have way more ruby  
processes running than you had ever planned, check out this patch.
On Jul 31, 2008, at 3:47 PM, E Durante wrote:
> Has anyone tried monitoring the ferret Drb server with launchd (OS  
> X)?Does anyone know if there is any limitation that would prevent  
> ferret from being monitored by launchd? I have tried many different  
> plists and none work. One starts too many ferret servers  and one  
> cannot start any server. If anyone has experience with this, any  
> information would be most appreciated.
>
> Thanks.
>
>
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