How to write NIST file using Matlab?

do anyone know how to write nist sphere file using matlab ? i need to
write new resample file in NIST format but i cant do it using matlab 7
cuz there is only  readwav,writewav,readsph  (to read sphere format
only).

i need new resampled 8Khz file as input for  gsm and celp encoder  .
can matlab run any '.exe' file because my encoder is in encoder.exe
file. Im using libsndfile library to encode my data. i just need to
send input file and set the coding format using batch command when
using the .exe file provided by libsndfile library.

thk u.