I just got my scanner working via usb (no wifi yet) by adding the ubuntu quantal repositories and updating libsane. I'm sure the latest version of libsane will probably be included in the next version of mint but if you need it to work now this is the easiest option (the other being compiling it from source code) Here's how:
WARNING!!! Make sure you make a backup and be ready to risk screwing up your system since adding unstable repositories is not safe!
First add Quantal to ypur apt soutces by opening a terminal and typing sudo apt-add-repository 'deb http://archive.ubuntu.com/ubuntu/ quantal main restricted'
Second type sudo apt-get update
Third type sudp apt-get install libsane. This will also download the required dependencies.
Finally type sudo apt-add-repository -r 'deb http://archive.ubuntu.com/ubuntu/ quantal main restricted'
This removes the Quantal repositories so you don't accidentally upgrade your entire system!
Now you should be able to use Simple Scan and it will detect your printer!
Now you should be able to use your Kodal esp scanner via usb.
To get wifi working, go to your printer and find out your ip address then open a terminal and type:
sudo pluma /etc/sane.d/kodakaio.conf
now edit the line that says
# kodak ESP5250 is usb 0x040a 0x4041
#net 192.168.1.68 0x4041
Make sure to remove the # from the second line and add the IP address to your printer. Mine was exactly the same except the last number, It's because autodetect doesn't work properly. Leave the 0x4041 (or whateveryours has) in place.
Now wifi should be working!



