Define update-rule on view

Hi there,
i got a table

xxtestobject(test_id serial,
test_name varchar(254),
test_active bool)

then i created a view

xxtest with
select * from xxtestobject where test_active=true;

i created a working rule for insert on the view.
now i want to implement a rule for an update.
the task is, that an update doesnt "update" the selected entry, it got
to set test_active to false, and insert a new row with the new data
and test_active settet to true.

i tried all the last view nights and now i'm not able to think any
more...

any ideas left ?

so many thanks in advance
Patrick