error in mexgdal functions.

Using mexgdal found here: http://www.mathworks.com/matlabcentral/fileexchange/6010-mexgdal and having followed their instructions I keep getting this error when running functions:

Error in mexgdal (line 1)
function z = mexgdal ( input_file, options )

Output argument "z" (and maybe others) not assigned during call to "mexgdal".

anybody know what is wrong?

[Walter Roberson]

Are you calling the routine directly or using one of the other routines provided there to do the call?

[Max1000000]

One of the other routines, gdaldump