show us ls -la initxyz.ora (I'm wondering if you linked to something different than you thought you did)
Edit: also see https://blogs.oracle.com/patch/entry/freeing_up_space_in_var (is it on the root filesystem? Are you checking free space properly? Remember, some utilities may not show deleted files that are still open).
Edit 2: How many files are under /var? You could be running out of inodes.