[Light OT]: JabRef problem

[K. Elo]

Hi,

I installed JabRef a couple of days ago and have a simple problem: I 
just cannot open my bibtex (.bib) file created and maintained with 
KBiBTeX. Each time I try the following error message appears:

 java.lang.NullPointerException
        at net.sf.jabref.imports.OpenDatabaseAction.openIt(Unknown Source)
        at net.sf.jabref.imports.OpenDatabaseAction$1.run(Unknown Source)

I have encountered no problems when opening the same file with KBibTeX, 
tellico or Pybligrapher.

Any hints?

Thanks in advance,

Kimmo