Comment 2 for bug 1077518

Same issue here. I had this before where it helped unlocking writer, calc etc from the launcher, starting them and locking them to the launcher again. However, since last update (currently on LibreOffice 4.1.0.4 on Ubuntu 12.04 64-bit) that workaround does not work any more.

What I found out:
When I open a .doc file then the icon is grouped (so just one icon), if I open a .odt I get a second one. So somehow this depends on mimetype and/or extension of the opened file. .docx also produces a second icon.