突然间，lumaqq输入密码之后就没反应了

tienchih

tc@Debian:~/Programs/LumaQQ$ ./lumaqq
tc@Debian:~/Programs/LumaQQ$ /home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:12: Unable to locate image file in pixmap_path: "stock_volume.svg"
/home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:68: Unable to locate image file in pixmap_path: "stock_brokenimage.svg"
/home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:83: Unable to locate image file in pixmap_path: "stock_quit.svg"
/home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:145: Unable to locate image file in pixmap_path: "media-previous.svg"
/home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:165: Unable to locate image file in pixmap_path: "stock_quit.svg"
/home/tc/.themes/MilkMint/gtk-2.0/../icons/iconrc:178: Unable to locate image file in pixmap_path: "media-previous.svg"
Exception in thread "main" java.lang.NullPointerException
        at edu.tsinghua.lumaqq.ui.sorter.ModelSorter.compare(ModelSorter.java:69)
        at edu.tsinghua.lumaqq.ui.sorter.ModelSorter.compare(ModelSorter.java:1)
        at java.util.Arrays.mergeSort(Unknown Source)
        at java.util.Arrays.sort(Unknown Source)
        at edu.tsinghua.lumaqq.widgets.qstyle.QTreeViewer.refresh(QTreeViewer.java:230)
        at edu.tsinghua.lumaqq.widgets.qstyle.QTreeViewer.setInput(QTreeViewer.java:500)
        at edu.tsinghua.lumaqq.ui.helper.BlindHelper.initTreeMode(BlindHelper.java:545)
        at edu.tsinghua.lumaqq.ui.helper.BlindHelper.resetMode(BlindHelper.java:729)
        at edu.tsinghua.lumaqq.ui.helper.BlindHelper.setTreeMode(BlindHelper.java:825)
        at edu.tsinghua.lumaqq.ui.MainShell.setClient(MainShell.java:321)
        at edu.tsinghua.lumaqq.LumaQQ.main(LumaQQ.java:149)


请问这是什么原因，怎么解决？