Mailbox: difference from usermin

Hi, I’m a new virtualmin user. I like this software and I’m writing the italian translation. I’ve a problem with mailbox, I saw that in usermin there are some features, like the address list or folders manager, that there aren’t in virtualmin mailbox. Is It a my configuration problem or a default setting?
Could I find a way to add this in virtualmin?
I think that a good webmail It’s usefull for the user.

Thanks, bye.