Are you opening ERF or JPEG?
I've noticed that the embedded thumbnail in the ERF (which is what the camera displays on the LCD) has a considerably different white balance setting than when I open the file using either Epson Photo Raw or Photoshop CS. That is to say, with both programs, when the files are first loaded and it displays the in-camera thumbnail, the photos have one color cast; once the program has cached the RAW data to produce a more detailed/accurate preview though, the color shifts noticably. I haven't noticed this phenomenon with any of my other digital cameras, such as my Canon 20D.
This has never been a concern for me since I only shoot in RAW, and adjusting white balance using the eyedropper is a given. And especially a non-issue since I mostly convert my R-D1 files to black and white. 😀