XBee RS232 Adapter to Uno

I have a USB XBee adapter connected to Tera Term on my PC acting as the coordinating radio and an Xbee RS232 Adapter acting as a router. If I connect both to my PC I can pass text from one terminal program to the other via the radios so I know they are connected.

I connected the RS232 adapter to my Uno using a serial breakout cable I made.

Pinouts for the connector are:

1 CD Input
2 RXD Input
3 TXD Output
4 DTR Output
6 DSR Input
7 RTS Output
8 CTS Input
9 +12VDC switched power out Output

Connections for the pins are:
1 3.3V
2 Uno D1
3 Uno D0
4 and 6 jumpered
5 Gnd
7 and 8 jumpered
9 open

The Arduino and RS232 Xbee are powered by seperate 9V wall adapters. I have 5 0.1microF capacitors across + and - to decouple the power supplies.

If I remove the radio from the adapter and wire it directly to the Uno, it works, but I want to use the packaged adapter for a clean install. I am running simple test code to beep a buzzer if the letter D is received. It works when the Uno is connected to the PC via USB and I type D into the serial monitor. I remove the USB to use the radio, since they are both running through hardware serial.

Can anyone see an issue with my serial terminations or hardware setup? I'm at a loss.