zipfile library - problem..

[Renzo]

Hi,
I'm working to create a backup function for a software; in particular, 
from a directory with 12300 files (Jpg, medium size = 250KB / total size 
= 2.90GB), i have to create a zip file.

I've decided to use the standard "zipfile" library to do that.
This is the code:

zipName = path.join(config.get('server.xbakPath'), 'backup.zip')
fileExport = zipfile.ZipFile(zipName,'w',zipfile.ZIP_DEFLATED)

#Insert images
listaImg = listdir( config.get('server.iPath') )
for file in listaImg:
     if not path.isdir(path.join(config.get('server.iPath'), file)):
         fileExport.write(path.join(config.get('server.iPath'), file), \
                          file)

#close ZIP
fileExport.close()

Unfortunately, after few minutes, i see this error message:
Traceback (most recent call last):
   File "C:\Python24\Lib\site-packages\cherrypy\_cphttptools.py", line
256, in run
     main()
   File "C:\Python24\Lib\site-packages\cherrypy\_cphttptools.py", line
452, in main
     body = func(*(virtualPathList + cherrypy.request.paramList),
   File "C:\pagine\utilities.py", line 162, in exportdati
     fileExport.close()
   File "C:\Python24\lib\zipfile.py", line 503, in close
     zinfo.header_offset)
OverflowError: long int too large to convert to int

Reading the error I've known that the error is generated calling
"fileExport.close()", that calls the zipfile module,
and into that module there is an exception.

For information: when code stops, the zip file has size = 3.177.950.237 
byte, but this size doesn't exceed ZIP limits:

the limits of ZIP files according to the folks who make info-zip:
http://www.info-zip.org/pub/in fozip/FAQ.html#limits

  statistic                             limit
number of files                        65,536
uncompressed size of a single file       4 GB
compressed size of a single file         4 GB
total size of archive                  256 TB
maximum path/filename length            64 KB

Have you any idea?
Oh, the O.S. is WinXP Pro

Thank you!.
Renzo