i only wanted to mention a close connection between the quicktime plugin and samba..only a hint
btw..i use soho 5.8. so by default the mplayer plugin is involved in ff and works pretty well.
i also can play quicktime videos in firefox...with the mplayer plugin
but quicktime needs the samba packet also installed. dont ask me why.
but for me the samba package is not necessary(no intern network with windows-boxes)..and i deinstalled it. afterwards ff loads a quicktime video too..until 100 percent..and then you cant play it.no reaction at all..
so i reinstalled the samba package reduced the rights (chmod -x rc.samba) and ff loads the quicktime video and plays it during the streaming process.as it should be...
so be careful and let your samba package on the box (and of course your mplayer package..thats necessary anyway)..and if you dont need it(the samba service)..deprive the execute right
this was my experience..nothing about writing home....i even dont know if this is only on my box...but if you encounter difficulties with quicktime videos...above is my solution