I use a set of scripts to accomplish this, still working out the kinks. Right now I mail entries I want to sync to an external server and process them there. Would be better if it could all happen on the device - but probably need the entourage specific sdk to get the right hooks to do stuff smoothly.

UPDATE: for anyone interested, here's the basic script I use: (runs on OSX, but should work on Linux. Needs fetchmail, imagemagick, mutt, and munpack)
(I originally had it compositing all the images into a single mail message, but found evernote was indeterministic about import order, so I switched to sending them all in and merging them manually)

#!/bin/bash
p=`pwd`
foo=`mktemp -d /tmp/journal.XXX`
d=`date`
t=`echo Journal $d`
echo $foo
cd $foo
fetchmail -u notes@XXXXXXXXXXX.com -B 1 -m munpack mail.XXXXXX.com
name=`echo *.pdf | sed s/.pdf//g`
convert -density 150 $name.pdf $name.jpg
for e in *.jpg
do
n=`echo $e | sed s/.jpg//g`
mutt -a $e -s $n -x -z ericvh.XXXXX@m.evernote.com < /dev/null
done
cd $p
rm -rf $foo
echo Done