[CentOS] ls returns file doesn't exist, find finds it??

Howdy,

I am getting some errors with find and ls command - such that find is
able to see a file whereas ls says the file doesn't exist. Initially I
was trying find and ls together as:
# find ./ -type f -mtime +15 | xargs ls

Similar behavior is seen even when I execute both commands separately.
Any thoughts on what might be wrong here?

--
thanks,
neubyr