G98 Error - "Overflow in Choose"

Dear All,
 Has anyone ever seen and solved this error in G98? I'm trying to run a
 single point SCF using DFT (functional makes no difference to generating the
 error) in conjunction with the WTBS "Well-Tempered Basis Set" for
 Iridium
 obtained from the EMSL Basis Set Library.
 Any suggestions?
 (Enter C:\G98W\l502.exe)
  IExCor= 408 DFT=T Ex=B Corr=PW91 ScaHFX= 0.0000
  ScaDFX=  1.0000  1.0000  1.0000  1.0000
  IRadAn=      0 IRanWt=     -1 IRanGd=            0 ICorTp=0
  Using DIIS extrapolation.
  Closed shell SCF:
  Requested convergence on RMS density matrix=1.00D-04 within1000 cycles.
  Requested convergence on MAX density matrix=1.00D-02.
  Requested convergence on             energy=5.00D-05.
  Virtual orbitals will be shifted by   0.200 hartree.
  Two-electron integral symmetry not used.
  Keep R1 and R2 integrals in memory in canonical form, NReq=     3319928.
  IEnd=   1010272 IEndB=   1010272 NGot= 104857600 MDV= 103681835
  LenX= 103681835
  Symmetry not used in FoFDir.
  MinBra= 0 MaxBra= 3 Meth= 1.
  IRaf=       0 NMat=   1 IRICut=       1 DoRegI=T DoRafI=F ISym2E= 0
 JSym2E=0.
  Overflow in Choose.
  Error termination via Lnk1e in C:\G98W\l502.exe.
  Job cpu time:  0 days  0 hours 20 minutes  5.0 seconds.
  File lengths (MBytes):  RWF=    6 Int=    0 D2E=    0 Chk=   11 Scr=    1
 Many Thanks,
 Daniel Tackley
 --
 Dr Daniel Tackley
 Computational Chemistry Group
 Avecia Ltd
 Manchester
 UK
 Tel: +44 (0)161 721 2541
 Email: daniel.tackley<<at>>avecia.com