The latest version of siesta can be found in:/share/apps/simulations/siesta-3.1/ though please note that it has been recompiled with a compiler different from the system version and thus requires certain libraries loaded first. Use the following as an example:
#!/bin/bash
#$ -N MoS2
#$ -o MoS2.log
#$ -cwd
#$ -j y
#$ -pe orte 4
#$ -V
#$ -S /bin/bash
source /share/apps/gcc/4.6.1/gcc-4.6.1-source.sh
/share/apps/openmpi/1.4.3-gcc-4.6.1/bin/mpirun -n $NSLOTS /share/apps/simulations/siesta-3.1/bin/siesta < MoS2.fdf
exit 0