It happens on udig 1.2-rc4.
After restarting uDig all the tools are deactivated.
To produce this error do the next steps:
-Create a new map with a polygon layer.
-Draw a feature and save the layer.
-Close uDig and launch again.
-Take a look at the tools and you will see all of then are deactivated.
It seems that this error is because all the tools can't activated. Take a look which condition on the activations is preventing the tool to activate (for example, the tool could look if the layer has a geometry and the layer return it hasn't a geometry, even if it really has, but the tool receives a false so it won't active.)