Comment 3 for bug 592057

By removing libqt4-assistant it also removes qtiplot and scidavis (ubuntu repository versions), since both depend on it.

as stated above:
ibqt4-assistant: Depends: libqt4-network (= 4:4.6.2-0ubuntu5) but 4:4.7.0~beta1+git20100522-0ubuntu1~lucid1~ppa1 is to be installed.
                     Depends: libqtcore4 (= 4:4.6.2-0ubuntu5) but 4:4.7.0~beta1+git20100522-0ubuntu1~lucid1~ppa1 is to be installed.

I could fix all the other stuff by de/selecting the correct packages manually. sometimes it is another name for libs, sometimes old transitional packages.