(New to vcloud, may be this is just the way it is)
When my director emails a user to warn them that a lease on a vApp is about to expire it it contains a line saying which one and when but the there's another line about how you can extend the lease with a full colon at the end but nothing else. Is there supposed to be a link for the user to click on? It looks like there should be one.
There should be a link, but depending on your user role it might be absent.
We do have an improvement request internally for these emails, but I'm not sure if there would be changes in the future.
What about earlier releases like 5.1.3? Currently, I am an Organization Administrator, and I don't see links in the Lease Renewal/Expiration Emails.
It looks like the enhancement request goes as far back as 1.5 generation. If you want/need this fixed, I'd suggest filing a support request.