See attached bitmap or run attached example code on Symbian^3 device. So far I have only been able to reproduce the issue on top of OpenVG graphics system. I am not sure whether the issue is related to the text painting routines, OpenVG graphics system or Symbian OpenVG implementation. The bug depends on the text being drawn, adding "." characters at the end of lines corrected the painting. Tested on top of QtQuick 1.1 branch sha e46c44f9538dbe5b44ce61d3a42403cfa471ae8b.
Text is being drawn through a following call stack: QDeclarativeText::paint() -> QDeclarativeTextLayout::draw() -> QPaintEngineEx::drawStaticTextItem(QStaticTextItem *).
See QDeclarativeTextLayout::draw() for more information.
The issue did not reproduce when I enabled QDeclarativeText text caching, by adding a following line to the C++ project.