[exim] sieve queries

Hi all,
I'm new to the list, so I must apologise if these questions have been
asked previously (I couldn't figure it out via google searches).

In our system at the moment, each user has a sieve script file which files
any mail
with X-Spam: yes into INBOX/spam.
Basically, I'm being asked to stop filing mail into an individual users
spam box, and instead, file it into the system.admin@???/INBOX/spam
folder.
I haven't been able to find the syntax for doing something like that
however (maybe something like: fileinto
system^admin@foo^bar^com/INBOX/spam ?)

Also, a more simple problem is how to regenerate the userscript.script
file. I've tried using sieveshell, but can't figure out howto regenerate
the userscript.bc file. I'm not sure sieveshell is working properly
(even running list returns no script files).

Thanks for reading.
Regards,
Paul.