Procmail Timeouts as Delivery Agent

Hello,

we're running procmail to deliver our mail. Is there a way to
make procmail timeout when a lockfile exists? The -t option
looks like it would queue _all_ email that could not be
delivered; we just want timeouts to be queued. Thanks!

--
Roberto Ullfig : rullfig(_at_)uchicago(_dot_)edu
Systems Administrator
Networking Services and Information Technologies
University of Chicago