lprng ignores input filter

[Kent West]

I can't seem to make lprng execute my if filter. It's not really a 
filter at this time, but only a test script to see if lprng is executing 
it. Here's my /etc/printcap:

lp
   :if=/home/westk/printtest
   :sd=/var/spool/lpd/lp
and here's my /home/westk/printtest "input filter"

#!/bin/bash
echo "Whoo-hoo"

Although I can manually run the script just fine, nothing I do seems to 
get the printcap/lprng to execute it.

Anyone have any clues?

Kent