Exchange 5.5

We recently blocked certain attachment extensions (.exe, .vbs, etc.) from being delivered to our Outlook 97 clients, and wanted to know if these blocked attachments, although they are not delivered to our employees, are put somewhere in Exchange. For example, if an employee states they needed an executable attachment to be delivered through Exchange, the system administrator can retrieve that file from that location on the Exchange Server and deliver it to the employee.

In addition, is there a way to block all attachments to certain Exchange 5.5 users?

Thanks,
Dan