cd /into/the/root.joomla/folder

SOURCEWWW=http://joomlacode.org/gf/download/frsrelease/10786/42690/Joomla_1.5.7_to_1.5.14-Stable-Patch_Package.tar.gz

wget $SOURCEWWW

SOURCEPKG=Joomla_1.5.7_to_1.5.14-Stable-Patch_Package.tar.gz

gzip -d $SOURCEPKG

SOURCEPKG=Joomla_1.5.7_to_1.5.14-Stable-Patch_Package.tar

tar -xvf $SOURCEPKG

rm $SOURCEPKG

Updated:

SOURCEWWW=http://joomlacode.org/gf/download/frsrelease/11395/45627/Joomla_1.5.14_to_1.5.15-Stable-Patch_Package.tar.gz

sudo wget $SOURCEWWW
SOURCEPKG=Joomla_1.5.14_to_1.5.15-Stable-Patch_Package.tar.gz
sudo gzip -d $SOURCEPKG
SOURCEPKG=Joomla_1.5.14_to_1.5.15-Stable-Patch_Package.tar
sudo tar -xvf $SOURCEPKG
sudo rm $SOURCEPKG