SMS Database Purge

I asset manage the software for my company and am not technical, but in an effort to assist my monitoring duties I am trying to find a solution. We currently use SMS 2.0 reporting to a SQL database for inventory reporting and have found that “old” data never purges from our system which makes following up on license compliance very difficult. I understand that this is supposed to be fixed in SMS 2003, but we were told that this was fixed when upgrading from 1.2 to 2.0. Does anyone have any suggestions on a work around that was successful in their environment? I would like to pass this on to our technical team for possible implementation. I know there are add-on products, but with the continuing challege to cut costs, any cost-effective method/suggestion would be appreciated. Thanks-