I'll look through those. The biggest problem we have encountered (and I'm new on this particular project - my predecessors have struggled with this through the last couple of years and it is one of the larger messes I've ever seen. I'm incrementally trying to clean all this up) is that the DOS apps are Clipper compiled applications. My company tried unsuccessfully a couple years ago trying to use samba. I'm not certain of details, but I was gold that the clients "didn't have enough free memory" to execute the Clipper apps. The DOS boxen are now connecting to a Netware 5.1 server using Novell's DOS client on a VG network. No, I didn't mistype that, a VG network.
Aside: our supplier for NICs and other gear for this network is eBay. And no, I don't sleep very well yet. :0(