My recommendation from experience is to install the management tools on a client PC (or 32 bit server). You shouldn't need to "manage" the DTS packages from the server itself, rather make changes on the client and save back to the server.

It installs fine on our dektop PCs, or 32 bit SQL 2008 servers, but we couldn't get it working on the 64 bit SQL 2008 server.

DTS works fine in SQL 2008 (we are using several in production). It is just a bit of a pain to manage the packages...