Newbie to Small Business Server

I am new to Small Business Server and one of the applications I am using in the interim is NT Backup for my small business server. I have configured a backup to tape and had a question concerning the exchange backup. i currently have chosen the e: drive which has my exchange data and checked the information store group as well.

My concern is that the data store backs up fine but when I look at restore backup sets the information store group shows up as 0kb. However when I look at the logs it shows the backup data for the information store group at the size it’s supposed to be. Does that mean it is getting backed up even though NT Backup shows 0kb in the restore screen??? I’m confused.

Thanks