Preedit text not visible on Qt5 QML text editors

Run QtDeclarative input method example under qtdeclarative/examples/declarative/inputmethods/spellcheck. Tap on the empty area to open virtual keyboard and type letters with the keyboard. Cursor moves, but no preedit text is shown. Happens with both TextInput and TextEdit elements. Preedit text should be drawn like normal text, but with an underline. Normal editor text is drawn correctly. This bug blocks text prediction work in many cases on top of Qt5. Tested on top of 32bit Ubuntu 11.04, QtBase repository commit a3e8f1ab0cc38c0d2e631d3e7f9e6379982204b7 and QtDeclarative commit 8801dd4f173a4e7676400dd18d76d89dfe3b3791.