pkunzip for x64 Matlab?

I have received a bunch of data and a pkunzip.exe file which I am supposed to run in Matlab using dos commands. I.e.:

dos(['pkunzip -o','data1.zip']);

But I am running Matlab x64 (R2011b) on an x64 win7 machine and the response I get from matlab is:

This version of C:\path\PKUNZIP.EXE is not compatible with the version of Windows you're running. Check your computer's system information to see whether you need a x86 (32-bit) or x64 (64-bit) version of the program, and then contact the software publisher.

Does anyone know how I can require an x64 pkunzip.exe for use in Matlab?

Thanks in advance

Answer 1

[Walter Roberson]

http://comm.pkware.com/pkzip-windows-business-download.html

"Does not require a license key to run the Standard Edition package"

[Jakob Sievers]

Thanks!

I will just have to purchase the full thing if I keep running into these types of datasets. Unless of course I find some free command-line unzipping tools that can be run in the same way.