Thank you. Since for this particular project I am using vs2013 I neglected to try to compile test project in QtCreator. Indeed, it compiles just fine. Looking into the list of includes in compile output I realized what the problem was. QtScript is included from four places, and when I added paths to VS that mimics the one in Qt everything worked.
c:\Libraries\Qt\Qt5.2.1\qtscript\include
c:\Libraries\Qt\Qt5.2.1\qtscript\include\QtScript
$(QTDIR)\include\QtScript