4. Long stay national visa for the purpose of taking up office
This concerns category D visas. With effect from 5 April 2010, they are also valid throughout the entire Schengen area for stays of up to three months.
As the issuance of this type of visa remains the sole responsibility of the Swiss authorities, the associated procedures remain the same. For further information on this subject, please contact the Swiss representation responsible for the applicant’s place of residence.
http://www.eda.admin.ch/eda/en/home/...is/manvi2.html
Sorry, I am not too good in this area, never having had that visa.