Laszlo,
It has something to do with the database in the logging software that points the prefix to the correct country. I don't use Win EQF, but I'm sure it's in the help files. Here is the download page for EQF:
http://www.eqf-software.com/pages.cfm?ID=17 Download and install the prefix.exe file (I believe).
73,
Terry, W0ZS