B 2.53 unable to save image/animation

Using Mac OS X 10.6.4 and Blender 2.53 I am unable to save F3 any rendered images. I get “unable to save” message.

Blender 2.51 doesn’t have that problem.

Anyone else having similar problem?
Solutions?
More information?

you are not alone.
(http://blenderartists.org/forum/showthread.php?p=1672744)

and there is a bug report: https://projects.blender.org/tracker/index.php?func=detail&aid=22539

worse thing is that it “destroys” files sometimes.
I’ve got several .blend files disappear after trying to save them. Luckily, there have been earlier backup copies to start over.