I checked out the existing project source code from SVN to a folder in my system. Then I opened eclipse. Import Project-> Existing Maven Project.
It imported without iss
Delete the metadata folder. Checkout again but select "Checkout as a project configured using the New Project Wizard" instead of "Checkout as a project in the workspace". Then a New Project wizard will open, type maven there and select "Checkout Maven Projects from SCM" preferably or "Maven Project". It should work. Remember this step should be performed for Maven Projects only. For normal Projects just select Java Project or whatever relevant type Eclipse project it is.