Event ID:9413 and OAB update on Exchange 2010

Hi, I´m changing the Exchange 2003 to Exchange 2010. I have the two systems working, but into the Exchange 2010 servers, when you try to update the OAB on the 2010 servers you get  this event " 9413" for some new DLs, but I can't find any information about " Event ID:      9413".

Error: 

Log Name:      Application

Source:        MSExchangeSA

Date:          22/06/2010 21:56:56

Event ID:      9413

Task Category: (13)

Level:         Warning

Keywords:      Classic

User:          N/A

Computer:      wptxexmbx02.ptx.fr.sopra

Description:

OABGen cannot find group metrics information for group '/o=sopra/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=PFO-TestOAB'. This is normal if the group metrics information of this group has not been generated yet.

Event Xml:

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

  <System>

    <Provider Name="MSExchangeSA" />

    <EventID Qualifiers="32768">9413</EventID>

    <Level>3</Level>

    <Task>13</Task>

    <Keywords>0x80000000000000</Keywords>

    <TimeCreated SystemTime="2010-06-22T19:56:56.000Z" />

    <EventRecordID>123419</EventRecordID>

    <Channel>Application</Channel>

    <Computer>wptxexmbx02.ptx.fr.sopra</Computer>

    <Security />

  </System>

  <EventData>

    <Data>/o=sopra/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=PFO-TestOAB</Data>

  </EventData>

</Event>

Does anybody what´s the problem, or do i must to do anything, please?

THX in advance.

Ruben