XML/WXR file splitter for Mac

I am trying to import an XML (also called WXR) file into WordPress but there is a limit to the size of file that can be imported. I read about a method for splitting these files here: https://www.ads-software.com/support/topic/wxr-file-splitter?replies=13
but the method does not seem to work
The method generates a message that seems to indicate that it works

File "wordpress.2011-05-31.xml" contains 1 items
Creating 5 files with at most 1 items each:
   Writing chunk 1 to file wordpress.2011-05-31_1.xml...
Done!

But it basically only creates one file (not the 5 that the message above seems to indicated that it did)

Any one know of a way to break up and XML file for import that works on the Mac. There is already a program for PC users but us Mac people seem to be out of luck on this one.