Command time limit exceeded - defer?

[Lister]

Hi all,

I got a notification recently that my box is bouncing mail, and the 
recipient got the following:

    Command time limit exceeded: "/usr/lib/dovecot/deliver"

This is quite an unusual situation, but this server should never bounce 
mail externally.  I've set soft_bounce = yes for now, but I'd like to 
disable bouncing for command time limit exceeded situations, because in 
those cases something is broken and I should fix it.

Short of setting command_time_limit to something absurdly high, is there 
a way to disable bounces for command time limit exceeded situations only?

Thanks
L