Working for a foreign consulate in the US

A client (US citizen) is beginning a job with a foreign consulate office in the US. They won't be paying her as a W-2 employee. It appears her income will be subject to higher Self Employment tax rates (full Social Security and Medicare Tax). However, the foreign consulate says it will reimburse her for the Social Security portion. Is the Social Security reimbursement (or supplement, or whatever you want to call it) also taxable as self employment income? How should it be reported? Thanks and happy tax season