I'm doing it, tried even with CM10, my CNA port(The other ROM I need to debug).Ypu need to have adb setup on your computer first for this to work.....
i have used it before
make sure phone is off
type adb logcat like i said before then
plug in your defy via usb then switch it on...
My ADB setup is normal, I need it to develop apps. After booting up adb logcat gets on fire, but nothing before it D: