Plugin updates: versions not being updated

I have a bunch of plugins for instance Gravity forms. I am getting the update messages. I (network admin) update them but after refreshing the page it still says i need to update the plugin although the new version is already installed. Is that a cache related issue? I have already deactivated w3 and cleared all caches.

I have just manually added a new version of gravity forms (ftp update) and the newest version is installed but when I look at the settings page of gravity forms it stills gives an old version number (3 versions ago). Do I need to change those values somewhere in sql or something?

Any ideas?