you have to use the dpkg commands, yeah I've fighted a lot with xD

I Have the files in the mmc2, in a subdirectory "programs" and a sub-subdirectory "quasar"...

gain root in xterm and write:

dpkg -i /media/mmc2/programs/quasar/libxinerama1_1.0.1_4.1_armel.deb

then:
dpkg -i /media/mmc2/programs/quasar/libqt3-mt_3.3.7_armel.deb

and in the end:

dpkg -i /media/mmc2/programs/quasar/quasar_0.96r172r31-maemo1_armel.deb

with me worked fine ^_^
(ps: relook to the filename in the command I've wrote, I may be wrong, but the command is right xD xD)