I have a 3800 going on 5 years now. This is what I'd suggest...
You can use this video for reference. It's not a 3800, but you'll get the idea: http://www.youtube.com/watch?v=eUysQFDH6u0
If you poke around you may find on specifically for the 3800/3880.
Okay, first you need to clean the capping station. The only way I know to get to it on the 3800 is to turn the printer on, and when the head moves the the left, pull the power cord. Hate doing it this way, but Epson doesn't let us get into the service mode on the 3800 via the lcd panel.
Start with distilled water. Carefully fill the capping station and dab with paper towels to pick up the excess ink. Clean the rubber seal and wiper blade. If you want a more aggressive clean, you can use "original" Windex in place of distilled water.
Now fill the capping station until you get a good puddle of water/windex. Turn the printer on (plug it back in), and let the head park. Turn the printer off normally with the power button, and let the machine sit over night (or longer).
You will most likely have to do a normal cleaning (run from the pc) after this. Then run some color swatches (flood an 8x10 in photoshop with the missing color and print to 8-1/2 x 11 plain paper) ... check your nozzles again.
If not clear, try again but use windex this time in the capping station. Let soak again over night, and repeat above.
If this still doesn't clear the nozzles, you may have to try a power clean from the printers control panel. But in 5 years I don't think I've ever run a power clean this way. The above has always worked.
Hope this helps!