[squid-users] Delay pools for local users

Hello!

I am trying to utilize delay pools of class 2 at per-user basis. All users are unix (localhost) users. They are identified by ident acl, for example:

acl vit ident vit

To turn the delay pools on I've included the following lines into squid.conf:

delay_pools 1
delay_class 1 2
delay_access 1 allow vit
delay_parameters 1 -1/-1 3000/3000

But delay pools do not work for me!

I'm sure that user vit is identified by squid. Because if I include the line 'http_access deny vit' into squid.conf,
squid denies access for (and only for) user vit.
 
I've read a lot of manuals related to delay pools and it seems to me, they work only if squid clients are connected to squid from the different IP
addresses (different machines). Am I right?

Have I any chances to solve my problem? What are the "class 4" delay pools which are intoduced in squid-3? Can this new feature be useful for me?

Thank you beforehand!

-- 
Sincerely yours, Vitaly Repin
Ice Brains Software, ltd