NT profile limits & IE5 index.dat issues

We use NT 4.0 with roaming profiles. 2mb profile limit. This is imposed by our parent office in Scottland. After awhile the index.dat files in the History folders grow to large sizes. The user cannot delete them since they are in use. How can this be removed w/o admin intervention???
Currently we have login as admin onthe WS and delete the History folder locally and on the users profile on the server. This is a pain.

Any Ideas???????