working directory

Acrobat starts always with ~ as the working directory. Because I keep all my pdf files in a seperate directory, I have to do quite some navigation before I can save them. This is especially bad as the Acrobat save as window displays all files including hidden files. Thus I would like Acrobat to use always ~/Documents/pdf as working directory. The .desktop file specification defines for Type=Application the entry Path= which is supposed to define the working directory.