RS-232 DB25 MUX connection question

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

I've got a MUX with a DB-25 connector on the back.  The manual tells me that
the pins are arranged as follows:

01  -  Alarm Input 1
02  -  Alarm Input 2
03  -  Alarm Input 3
04  -  Alarm Input 4
05  -  Alarm Input 5
06  -  Alarm Input 6
07  -  Alarm Input 7
08  -  Alarm Input 8
09  -  RS-232 RX Input
10  -  RS-232 TX Input
11  -  RS-232 RX Output
12  -  RS-232 TX Output
13  - VCR Trigger Input
14  -  Alarm Input 9
15  -  Alarm Input 10
16  -  Alarm Input 11
17  -  Alarm Input 12
18  -  Alarm Input 13
19  -  Alarm Input 14
20  -  Alarm Input 15
21  -  Alarm Input 16
22  -  Alarm Hold Input
23  -  Alarm Output Common
24  -  Alarm Output NC
25  -  Alarm Output NO

I'm trying to hook this up to a PC using a 9 pin serial port with a DB25
adapter.  I looked at the diagram for the standard RS-232 serial port
pinouts:

http://www.internet-remotecontrol.net/pccompci/rs232-cable-technology.html

At first I had hoped they used a standard configuration and chose the
location for the RS-232 lines based on where they appear on standard PC
DB-25.  But pins 9-12 on a standard connector are test pins and whatnot.
The MUX pinout also uses pin 1 for an alarm channel where the standard has
it marked "ground."

Does anyone have any suggestions how to wire the MUX pinout above so that I
can communicate with it via a 9 or 25 pin PC serial port?

I'm using a 25 to 9 pin serial adapter, FWIW, because I already have a DB25
connector with a ribbon cable coming out that I can easily wire to the MUX
until my Winford Engineering breakout box arrives.

TIA!

--
Bobby G.