Connecting GSP/MP console port to serial switch

[John Eaton]

We have group of rp74xx and N class servers that I am trying to connect to a Lantronix Secure Serial Switch (SCS1600). I have them connected, and can access them via the switch, but they won't automatically disconnect when you logout of the console either from the OS prompt, or the GSP/MP prompt. I've got a call open with HP, but I was hoping someone else has been through this, and might have a shortcut to the needed results.
Bottom line is that the console port will not release DTR on a logout, even with HUPCL set for both getty and stty. Man page says that HUPCL means the 'line is hung up on the final close', but I don't see any signal changes (on rs232 breakout box). I asked the HPRC if I should be using the modem port instead, and they said no. I know it supports hardware signals....
The SCS1600 won't release a port without being told to do so, and they support DSR/DTR to do so. If a port is not released, it can't be used again until it is released. Creates a hassle - connect to port, do your work, exit, then login to switch mgmt port and disconnect session. Just not the right way to do it, especially since this setup is intended for emergency remote access to the console, not general use.
Anyone 'been there, done that'? Thanks!