Fastest way to "find / -mtime +7".....

[Ed Walker]

I've got a lot of small maildir files stored on a reiser-fs  
partition.  Currently we expire out the old stuff using
    find /mail -mtime +7 -type f -print0 | xargs -0 rm -rf
this is pretty slow on reiser, at least compared with ext2/3, and I  
understand that it may be because the find command returns the names  
in a non-optimal order (ie readdir order?).

Is there something we can do to speed it up?  Any suggestions?

Thanks-

Ed