[Ashur]

something wrong with your server setup, it's failing to execute properly
which happened to me on the old host which only works after complaining to my host and they fix it up then couple days come back again, so i had to dump them and go with different host but then it wasn't just the poll there were more things not working

only thing to suggest to use php5 if you're not doing that
and make sure php safe mode is off
also check if your cache is writable