Unknown resource "walltime" when running in parallel.

Hi,
I've been trying to run I-TASSER using the parallel runstyle since I'm working with a computer cluster and serial is too slow to be practical. Whilst serial works without issues, every run I've tried to do in parallel gives me an error when it tries to do the parallel threading. Output from my most recent run from the threading stage onward was this:

3.1 do threading
start parallel threading PPAS
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading dPPAS
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading dPPAS2
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading Env-PPAS
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading MUSTER
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading wPPAS
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading wdPPAS
Unable to run job: unknown resource "walltime".
Exiting.
start parallel threading wMUSTER
Unable to run job: unknown resource "walltime".
Exiting.
only 0 threading programs have output, please check threading programs

This problem occurs whether I run on the queueing system (using qsub etc.) or simply run on the server without qsub. I've looked at the installation and implementation guide and haven't found anything that suggests any potential threading problems specific to running in parallel. The script I'm running is as follows:

#!/bin/csh
#
/biol/programs/I-TASSER4.0/I-TASSERmod/runI-TASSER.pl -pkgdir /biol/programs/I-TASSER4.0 -libdir /biol/programs/I-TASSER4.0/ITLIB -java_home /usr -datadir /biol/people/co631/sequence/parallel -runstyle parallel -usrname co631 -seqname parallel

Can anyone tell me what the cause of these errors might be and how to resolve it?

Many thanks,
Callum.