Well, all I did (on my Mandrake 9.1 system)...
in my /home/username/.profile
and it worked just fine.
I've been reading some of these posts and it seems that a lot of people are having a hard time with this, creating a whole mess of other variables (JAVA_HOME...etc) and modifying a bunch of other "profile" files all over the place and creating other *.sh files just to do this...
Its not like the good old days where you just double clicked the "setup.exe" and the whole app. installed on its own and put a nice icon on your desktop