I've some more info on the "MaxOutstandingR2T value. The rfc states it's a positive int, the open-e implementation returns 0.

The solaris drive only checks on positive numbers.

if (isp->sess_type == ISCSI_SESS_TYPE_DISCOVERY) {
/* EMPTY */
} else if (strcmp(value, "1")) {
cmn_err(CE_WARN, "iscsi connection(%u) "
"login failed - can't accept "
"MaxOutstandingR2T %s",
icp->conn_oid, value);
return (ISCSI_STATUS_NEGO_FAIL);
}
text = value_end;