Yes for internal connections, but also for using the "recommended" DB-19 to IDC-20 extension cable from IEC: http://www.iec-usa.com/cgi-bin/iec/fullpic?ezV2CFGH;L1561;6The IDC connector is if you wanna connect it internally, right? If so, you probably don't need the case.
If you know of a DB-19 to DB-19 extension cable, I would love to see it! That IDC-20 cable from IEC is the only one I've found that works.