Spreadsheet_Excel_Writer New Line Problems on Windows

I am using a windows machine provided by a hosting company. I had to upload all files including PEAR.php from a OSX machine on which I had performed all my tests. On the Mac I was able to produce the first example from the documentation without problem, but on the windows machine the file produced reads as text if set with http headers, and if written to disk and then FTPd down to either a Windows or Mac and open with excel I get an error saying the file is not accessible. When I open the file with a text editor and compare it with that produced by my Mac (and which works) ther appeares to be a difference in the new line terminations. New lines in the Mac version are special chars in the Windows version but dont cause a hard new line. Any idea? Thanks, Jason