Messages in Linux dmesg

Hi all.
I have a RHEL 5.4 box running about 130 digiport servers.
I have inherited this box from another someone else and and still trying to find my feet.
I have notice that in my dmesg file, i have the following types of entries:

dgrp: net receive: Sent Reset to node gg - Improper Window Sequence
dgrp: net receive: Sent Reset to node NN - Improper Window Sequence
dgrp: net receive: Sent Reset to node PP - Improper Window Sequence
dgrp: net receive: Sent Reset to node VV - Improper Window Sequence
dgrp: net receive: Sent Reset to node xx - Improper Window Sequence
dgrp: net receive: Sent Reset to node ww - Improper Window Sequence

Can someone tell me what this means?
The driver I am using is V1.9-20
TIA.