Drive out of space

[John Portwin]

Our /var drive partition ran completely out of space earlier; it houses
the queue and the logs. /home is on a different partition, and has plenty
of space. A quick rm -rf sorted that one out, and a new drive is on its
way in, but..

How would this have affected qmail? Could we have lost any mail, or
would it be deferred (to our secondary MX)?

Thanx
John