[CentOS] send existing root email to another user

Hi all,

I'm running Centos 5.4
I have a pile of emails in my root users /var/spool/mail/root file
I need to send this all to another address (preferrably external but 
local would possibly do)

I have searched a lot but can't find any way to do this. I have set it 
so future emails get forwarded to my external address but I also need to 
shift the existing emails.

Thanks
Kate