[ic] Cookie on 4.8.3

[interchange-users@interchange.redhat.com (Barbara Picci)]

Hi,
we had a shop on Interchange 4.6.5 that works fine on a BSD server 
with a space provider.
now we've a new Linux dedicated server with Red Hat 7.1 and the last 
Interchange version 4.8.3.
All works fine but there is a problem with persistent cookies:
we need to maintain cart closing browser.
In version 4.6.5 no problems, cookie was persistently maintained with 
mv_save_session.
In 4.8.3 we red thet we need to add set-cookie directive, like: 
[set_cookie name="MV_SESSION_ID" value="yes" expire="[time gmt=1 
adjust='+2190']%a, %d-%b-%Y %H:%M:%S GMT[/time]"].
- Is it correct?
(we tried to name it not mv_session_id but another name and the 
browser can't recognise the order)
We put it in result.html and inside the form.
- Is it the right place?

It generates cookies, but, closing and reopening  browser, it 
generate another cookie that overrides the previous and clear the 
cart.

Can anyone give us any suggestions?
Thanks in advance

Barbara