how to enlarge simulation time limit of ncsim?

I have a very large simulation case which should run 12000 seconds (simulation time, not CPU time). But I find that ncsim will stop after about 9223s. It seems that ncsim(e.g. irun) has a maximum simulation time limit of 9223s. Does anybody know how to change this value? I have tried another simulation tool -- VCS (Synopsys), it does not has this limit.

Thanks!