I keep a couple of searches out on Monster.com going, just to keep some low-level antennae out on the job market, and I am amazed at the picky, specific/exotic, unique-to-their-company knowledge that many job posters are looking for.
“Oh, we are looking for a mechanical engineer with 6 years experience in designing left-handed vreeblefetzers in Pro/Engineer, who also has at least 3 years of experience in designing parts for GE retroencabulators…” etc etc for 3 paragraphs. Obviously I am not qualified for the job because obviously the guy who used to do the job just retired and they are looking to replace him… EXACTLY.
In my current work I do both ME and some CS-type work, depending on the assignment, but this work is heavily flavored by the my-company-specific nature of the expertise I have to use. (Printer-design technology, in-house CAD parts database and standards, etc). I don’t care how good you are, if you are migrating to another company which is operating in even a slightly different technological area you will have to do some training up in the in-house expertise.
Not to say all Monster postings are this unreasonable, but it is pretty rare for me to see a posting where they ask for Basic Skill Set A and say “we will train you into our company-specific skills.”
But I am told most job postings are written by script kiddies in Personnel with no clue about the actual job anyway.