trackName lost

Prior to r2737 and after r2732 the <trackName> tag gets moved into the <Instrument> tag when saving a score, confusing MuseScore on next loading of the score and raising console errors like

line:237 col:17 Instrument:Part:museScore:: Unknown Node <trackName>, type 1

If the score is modified and saved again, the trackName info gets completely lost => dataloss => critical priority.

STR:

1. Create a score, add a couple of instruments, write some music.
2. Press 'i' to check stave names.
3. Save & close the score and reopen it.
4. Go to step 2.

Actual results:
The aforementioned error in the terminal after step 3, staves are nameless in step 4. Modifying the score and saving it again after the step 3 will eradicate every trace of trackName in the XML file.

Expected results:
The same stave names after step 4 as after step 2.

MuseScore r2741 on Ubuntu 9.10