The reference that you listed is from the programmers guide, and is a snippet of C code, not a shell command. What you need to do is make sure that your paths are correct for the tk packages, and that you have all of the dependancies loaded. Are you running from a download directly from their site? Suse uses rpms, so installing scilab from a properly created rpm should resolve most of the dependancy issues. Try downloading from http://rpmforge.net/user/packages/scilab/.
I haven't found a package specific to Suse 10 64 bit edition (or any other 64 bit rpm based distro for that matter), but someone may have built one.