Computer engineering job with only a computer science and physics degree?

you could probably get a job in that then, yeah

Not impossible but you will be lacking knowledge in some of the main topics in computer engineering: computer architecture, digital circuit design and electronics.

I know some CS programs offer course electives in digital design (FPGAs, CPLDs, microprocessors, Verilog, VHDL, etc) but you will still need to take a few more circuits courses besides the Intro to Circuits course taken during lower division.

You do not need P.E. certification to work as a CpE, but without the knowledge on the topics mentioned before you will be nailed at the job interview. By the way, I don't think the degree in physics will do much for you in that field.

Well you don't need PE qualifications to do alot of engineering jobs, and that goes for other types of engineering as well. That's not saying much. Doesn't mean you don't need an engineering degree which is required on many CE type job postings. I heard one person say that the engineering degree itself can be viewed basically an engineer's first certification. So it does mean something otherwise there would be nothing special about engineering degrees. Having said that though, since CE is relatively new if you somehow could obtain the requisite hardware knowledge as stated above you could probably still slip in somewhere.