This is a thunderbird extension which can verify the autenticity of the email source
This extension don't deal with the hacked email accounts
Go to Tools > Addons > Addons Menu > Install Addon from File and selecte fakeaddress.xpi file
To check whether the email is fake or not, you have to select the wanted email and click on "Check Now!" button that you will find in the toolbar. If it's a fake email, and alert dialog will appear to provide you some extra information about the email. If nothing happens, you're good. Note that it only support google's servers, (hard coded).