Could not load nl strings from resource module: nhttprs_nl

I have found several threads in this forum on this item, but not a real answer :

Since I’ve upgraded my Domino server from 6.02CF1 to 6.02CF2, the folowing message appears regularly in the server log :

Could not load nl strings from resource module: nhttprs_nl

The 6.02CF1-server was installed with the 6.02CF1 dutch Language Pack (=nl)

The 6.02CF2-server was installed with the 6.02CF2 dutch language pack.

This seems to cause no troubles at all, but I would like to know what’s causing this message. I never had it before.