Schema Dump

We recently upgraded to Rails 2.1. When dumping the schema ( rake
db:schema:database) from our database I expected to see the command to
create the schema_migration table. Why is this table not in the schema
dump file ? Also, the schema_version is still in the file, but not in
the database ?

the ruby schema loader knows that in needs to create the schema
migrations table so why would it include it ?

Fred