[Dovecot] Sieve, before script - Can it include "personal" scripts?

Using sieve_before, can the script it references include a file from the personal space?

I want to set some parameters (by user using the variables extension) there to control what the before script does, so, every user would have the file in their personal include space.

If not, is there another way?

Can the sieve_before and sieve_global_path be set from userdb extra fields?