Marking a message read when delivering to a Maildir

Howdy,

I have searched the web and cobbled together a process to deliver a 
message to my Junk folder (Maildir), then immediately mark it read. 
However, I've run into a small problem, the filter runs faster than the 
actual delivery, so I have to spin waiting for the file to appear. My 
filter is below.

I'm wondering, is there an easier/better way to do this in the first 
place? Is it ever contemplated to add this as a feature?

Thanks,

Doug

if (/^X-Spam-Status: Yes/:h)
{
         cc Maildir/.Junk
         `until [ -f ${HOME}/Maildir/.Junk/cur/1*:2, ]; do sleep 0.1; done`
         `for m in ${HOME}/Maildir/.Junk/cur/1*:2,; do mv $m ${m}S; done`
         exit
}

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