Change Maildir to another folder?

I have attached via FUSE and Ftab my s3 bucket to my virtualmin server on an EC2 instance and it works perfectly for backups etc. How can I put the Maildirs for the Virtual Servers there too. please? I.e instead of /home/vserver1/Maildir and /home/vserver2/Maildir have them in /s3bucket/vserver1/Maildir and /s3bucket/vserver2/Maildir.