File save dialog always starts from system root (Mac OS 10.6, 2.55b)

Just a simple thing I guess, but googled for ages without any success. Whenever I started a new project (i.e. File/New) and want to save my work, Blender’s file save dialog always stays at UNIX system root. OK I have the list of recently used dirs and my favorites, but it is a little bit annoying for a beginner running through all the tutorials.

Environment:
Blender 2.55b
Mac OS 10.6scripts: [’/Applications/blender 2.55b.app/Contents/MacOS/2.55/scripts’]
user scripts: None
datafiles: /Users/kay/Library/Application Support/Blender/2.55/datafiles
config: /Users/kay/Library/Application Support/Blender/2.55/config
scripts : /Applications/blender 2.55b.app/Contents/MacOS/2.55/scripts
autosave: /Users/kay/Library/Application Support/Blender/2.55/autosave
tempdir: /tmp/
I have a parallel installation of 2.49.
What is wrong with my configuration?

Thanks for your help

Kay