Why is "importFee" 0 for an external message?

[macaujack]

After I send an external message to a wallet contract (created with blockchain.treasury()), I console.log(result.transactions[0].inMessage), and I get

{
    info: {
        type: 'external-in',
        src: null,
        dest: EQAU9I1xishP07ROGxoqrrRviknz75czKC2OdVVF5O8wDY3P,
        importFee: 0n
    },
   init: null,
   body: x{8241DBA49F37E6CFD550DE2DA73C0A33EBAF51391D22686849BE151350CB2CE3C_}
       x{D001}
        x{62004C0F1A94822F736A3ABC8A0F02C3F897E74E663A2990FD58153AD92C4B6CB4DF2017D78400000000000000000000000000004392B9EF800693BE77F465035B2E7E0ABD4D6A8DBCD909BD7D348EB3A49ED9E5363875FEA41_}
    }

As far as I know, for an external message, there should be an import fee (also called "in forward fee"). But why is importFee here 0?

[AlonzoRicardo]

I got the same issue