[web2py] cache.shelv problem

[frasse]

I hade a working application for some time now. now it stop working
and it give the following error.
the cache directory is exist and access permission is 775 to it .

Traceback (most recent call last):
  File "/home/www-data/web2py/gluon/main.py", line 485, in wsgibase
    serve_controller(request, response, session)
  File "/home/www-data/web2py/gluon/main.py", line 188, in
serve_controller
    environment = build_environment(request, response, session)
  File "/home/www-data/web2py/gluon/compileapp.py", line 257, in
build_environment
    c = environment['cache'] = Cache(request)
  File "/home/www-data/web2py/gluon/cache.py", line 376, in __init__
    self.disk = CacheOnDisk(request)
  File "/home/www-data/web2py/gluon/cache.py", line 261, in __init__
    os.unlink(self.shelve_name)
OSError: [Errno 2] No such file or directory: '/home/www-data/web2py/
applications/myapp/cache/cache.shelve'


Thanx
Frasse