It turns out the active content issue is caused by that firmware contains only k3 hardware configuration and does not to recognise other devices.
Here is a method to run active contents on 3.2.1 firmware.
unzip k3's KindleDeviceServicesShasta-1.0.jar
unzip DXG's KindleDeviceServicesTN-1.0.jar (TN means TuringNell)
cp dxg/res/* k3/res/
cp dxg/...../capability/DeviceCapabilityAdapterImpl$1.class to k3/../capability
cp dxg/...../hardware/*.keyboard.json k3/...../hardware
Now is the most technical part of this patch.
find the string A3P5ROKL5A1OLE in binary file
replace it with the device type number of your device
(I don't know a good way to find out this number of your device, but
see /var/log/messages or google "Device Type (device_compatibility_browse)" may help)
then overwrite the shasta keyboard json file by the json file of your device.
for example, DXG users should cp miranda.keyboard.json shasta.keyboard.json
zip back the k3 jar files and find a way to replace the jar file on your kindle.
Every Word and KindleNote are tested and work fine on my DXG (with a chroot 3.2.1 framework).