Fix gcmc incompatible with given pair_style

Dear users and developers:

I am trying to use GCMC to insert hydrogen atoms in a simulation that
uses pair_style airebo. I get the following error message:

ERROR: Fix gcmc incompatible with given pair_style (../fix_gcmc.cpp:315)

The lammps documentation page for fix gcmc does not say that there are
any restrictions about the pair_styles that the fix can/cannot be used
with. My input script is appended below. Any help in fixing this is
deeply appreciated.

units metal
boundary p p p
atom_style atomic
read_data hydrogen.lammps
pair_style airebo 2.0 0 0
pair_coeff * * CH.airebo H
mass 1 1.0000

thermo 10

fix 1 all gcmc 100 100 100 1 311313 300 1.0 0.1 pressure 1
fix 2 all nvt temp 300 300 0.1

dump 1 all cfg 1000 ${pref}_*.cfg mass type xs ys zs
dump_modify 1 sort id
dump_modify 1 element H

run 10000


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