HELP!! What is wrong with my Pentax DSLR K100d???

Hopefully someone here may be familiar with the issue that suddenly cropped up with my Pentax K100D DSLR. Have a look at these pictures below. I just noticed this problem on a recent trip last week. You'll notice the lines and the magenta coloration on the right side. It is more prevalent in pictures that are back lit or in low light, but you can see well lit images have the lines. I've tried 2 different chips and get the same result. I'd say 85% of the images I take have this issue. Prior to my trip last week the last time I used the camera was at Christmas. I looked at those images and about 20% have lines but not the magenta coloration.

Pete

http://i13.photobucket.com/albums/a2...t/IMGP8682.jpg
http://i13.photobucket.com/albums/a2...t/IMGP8704.jpg
http://i13.photobucket.com/albums/a2...t/IMGP8779.jpg
http://i13.photobucket.com/albums/a2...arco200959.jpg
http://i13.photobucket.com/albums/a2...arco200959.jpg
http://i13.photobucket.com/albums/a2...rco2009178.jpg