Okay do this. It may fixes your problems.

Open up xterminal:
root
apt-get update
apt-get -f install

this will go through and look for any broken packages and updating it to the current package of anything related to hildon-desktop. I am assuming Virtual keyboard is part of hildon-desktop.


Update:
look for these apps in the screenshot below in your App uninstall area. remove them and reboot the device.

If no changed is made then open Xterminal and type:

root
apt-get remove ukeyboard
aptfget install ukeyboard
reboot

done.