This is actually a path problem.
If you have installed the "vanilla" TeXLive, it is not enough to add the new PATH in your
.profile file (or any configuration fill used by your shell like
.zshrc...) because this configuration file is not used by your graphic environment (gnome, kde, xfce...).
For graphic environment, there is no such file for each user (omission in freedesktop?)!
In Debian/Ubuntu distribution, you can add the new PATH in the
/etc/environment file (via
/usr/local/texlive/2012/bin/x86_64-linux is the TeXLive path on x86_64 architecture. On i386 architecture, choose