Valid platform ports are not listed by QSerialPortInfo

I built the qserialport closely with instruction (http://qt-project.org/wiki/QtSerialPort_Russian) in debug mode. After lib's installation I run example app "terminal" but in "Settings" dialogbox the list of available ports is empty. Also example app "cenumerator" shows:

enumerator
Total number of ports available: 0

But in the same time "gtkterm" shows all ports on my machines correctly (ttyS0-ttyS10) and for test purpose I can connect 2 gtkterm via socat easily.
When I press "Connect to serial port" button I always got "error code:10" ("UnknownPortError"?).
This issue is reproduced under any user, sudo and root as well.

In WinXP env all works fine.