[gmx-users] atomtype names case INsensitive?

[gromacs query]

Dear All,

I have a complex A-B (not covalent bonded)

I want to use oplsaa.ff atom types original for A and all are in .top files
in which some parameters are changed and I have another directory with
modified just atomtype names oplsaa.ff files (for B) that is ffbonded.itp,
ffnopnbonded.itp, atomtypes.atp are modified with all the atomtype names
with lowercases thinking that it will avoid over riding and mixing of
parameters (as some of angles and dihedrals are common).

for example (there are many)

WARNING 4 [file A.top, line 342]:
  Overriding Ryckaert-Bell. parameters.

showing old and new values. The old values are from modified
oplsaa.ff/ffbonded.itp in which I have already used lowercase atometype
names.

Using gmxdump I can see system B is using modified oplsaa.ff. So does this
mean Gromacs is case insensitive as I get warning even I used lowercase
letters?

regards,