PAL To NTSC

I just successfully converted 25 fps PAL source to 24 fps progressive NTSC dvd using:

 -f 23.976,1
 --export_fps 23.976,1
 -x mplayer="-speed 23976/25000"

and

 mplayer -ao pcm -vo null -vc dummy $file.avi
 (output goes to audiodump.wav)
 # (24000/1001)/25 = 0.95904
 sox input.wav output.wav speed 0.95904
 # maybe you need to upsample to 48 KHz as well
 sox audiodump.wav -r 48000 output.wav resample speed 0.95904

 .
 ffmpeg -i $file.wav -acodec ac3 -f ac3 -ac 2 -ab 192kb -ar 48000 $file.ac3
 (or)
 toolame -p 2 -b 384 $file.wav $file.mp2

Dvdauthor showed the audio stream length to be too long by a factor of 1.0427 (25000/23976), but the dvd played fine in several commercial dvd players, so this appears to work!!