Hi Igor,
SNMPv1 and SNMPv2 have different error codes.
There is no "End of MIB" at SNMPv1, so it seems the message is what snmpWalk prints in case of SNMPv1 error code "NoSuchName".
In this case the client is requesting the next MIB object, and since it was the last one, v1 returns "NoSuchName" (= there is no successor to this one).
SNMPv2 has a better "error" reporting for this, it returns
"No more variablesvleft in this MIB View (It is past the end of the
MIB tree)"
which means this was the last object known to the agent in all its MIBs.
Dirk