Database log truncated

Recently we've upgraded SQL 7.0 to SQL 2000. We use a Database Maintenance Plans to backup the databases and transaction logs. Everything seems to be working, but Im getting an error message in the event viewer that has been described in Microsoft Knowledge Base article 818202 "PRB: A'Database log truncated" Error is logged in the Event Log When you try to Backup the Transaction Log. The article describes the cause of this warning, but does not give any fix or some kind of work around. Does anybody knows what to do or may be had this problem before? Please help. Thanks a lot.Switch your database to simple recovery.
backup the transaction log with truncate_only
Switch your database back to Full recovery.
run your maintance plan.|||As the article states, the cause for this entry in Event Log is the presence of either TRUNCATE_ONLY or NO_LOG.

Look into SQLMAINT command line utility, it gives you higher level of control, and you can use it against Database Maintenance plans as well.|||Make sure you issue full backup statement once NO_LOG or TRUNCATE_ONLY is issued on Tlog.|||Originally posted by rdjabarov
As the article states, the cause for this entry in Event Log is the presence of either TRUNCATE_ONLY or NO_LOG.

Look into SQLMAINT command line utility, it gives you higher level of control, and you can use it against Database Maintenance plans as well.

Yes, the article states that, but where I can see presence of these two options(TRUNCATE_ONLY or NO_LOG). I mean this job was created by Maintenance plan and is running as :

EXECUTE master.dbo.xp_sqlmaint N'-PlanID E4B335C8-20F2-4E29-A332-BD4778515EF5 -Rpt "D:\MSSQL7\LOG\DB Maintenance Plan20006.txt" -DelTxtRpt 2WEEKS -WriteHistory -VrfyBackup -BkUpMedia DISK -BkUpLog "D:\MSSQL7\BACKUP" -DelBkUps 1DAYS -BkExt "TRN"'

And if i use SQLMAINT utility to run the Database Maintenance plans what swich should i use for TRUNCATE_ONLY or NO_LOG options?

One more thing i don't understand it only happened on one server and 2 other works just fine.|||That's a mystery. Did you try to run the job manually? Could it be that it's not your job that fires NO_LOG, but some other maybe even ad-hoc statement issued from QA?|||http://support.microsoft.com/default.aspx?scid=kb;en-us;288577 KBA to troubleshoot Maint.plans.

HTH