Will Firefox spoof? OT?

Hello SuSE people, Need to access some government websites that only allow IE6 or whatever to fill out forms etc. (Will they ever learn/ get modern/ whatever?? ) (Really sad how Microsoft controls through the ignorance of bureaucrats ) Anyway, I remember seeing somewhere that Mozilla could "spoof" these sites into thinking they were dealing with (Ugh ! ) the MS browser. Spent a lot of time with Firefox trying to see if it could make it "spoof" the site. Didn't find any or was not obvious to me. If not, can Konqueror do it? or Opera? Bob S.