Serrations are not nearly as hard to sharpen as people make out. I mean, no it's not as easy as a plain edge, but it's not hard. It's fine detail work and a little tedious...but very satisfying if you have any sharpening junkie in you.
Get a sharpening slip of a couple of grits or get a DMT serration sharpening tool (it's a cone shaped diamond rod about 3 inches long...a very pointy cone). Go at it easy and get a nice little apex on each curved serration. Then move to a finer slip (I just use the SharpMaker white rods) and very carefully work the edge of each individual serration. Then get a chopstick or a bamboo skewer and put some green compound on it. Strop each serration. Then tape up the serrations and sharpen the plain part like normal. Take off the tape and strop the whole thing like normal.
I count 10 serrated portions...10 little "recurves". Give each one about or two minutes of your time and that great knife will be very sharp. Again, it's detail work but to restore a beauty like that, it will be well worth a half an hour of your time.
If you use diamonds, go easy. If you use the brown SharpMaker ceramic slips you can really go at it pretty hard without altering the profile of the serrations.