There is a small GPS blocker installed in all CJ1-2-3 tht is designed to only permit apprived GPS receivers to operate in the EU airspace.
It is a different version of SA, that we was controlled by the USA, this is controlld by EU.
Hope this is helpful.
Full details at:
www.wtf.aero.com.net
sorry for the delay but been away since 1st April.
glf