Fedora sevens xfce4 package is a steaming pile of incompleteness.

Here are very rough steps to getting xfburn going.

wget http://www.paldo.org/paldo/sources/libburn-1/libburn-0.3.2.tar.bz2
wget http://www.paldo.org/paldo/sources/libisofs-1/libisofs-0.2.4.tar.bz2

do the ./configure && make && make install on the above libs

svn co http://svn.xfce.org/svn/xfce/xfburn/trunk xfburn

cd xfburn
./autogen.sh

# the pkg_config_path is needed so xfburn can find the pkg-config file for libburn-1
PKG_CONFIG_PATH=/usr/local/lib/pkgconfig ./configure

# you need to add /usr/local/lib so that xfburn can find the libburn ... libisofs libs.

create a file /etc/ld.so.conf.d/libburn.conf and add the the following content
/usr/local/lib

# then run
sudo /sbin/ldconfig -v