Update Rollup 5 for Exchange 2007 SP1 is now released

I was so good without sp1 on my exchange 2007. no errors no bugs no nothing. But because of the public folders management I had to upgrade yesterday to sp1 and since I made it this far I thought that I should apply RU5.
Since yesterday i have only ASp errors in my logs.
Any ideas what I should do at this point ?
This is just a sample

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hread information:
   Thread ID: 9
   Thread account name: NT AUTHORITYSYSTEM
   Is impersonating: False
   Stack trace:    at Microsoft.Exchange.Clients.Owa.Core.Utilities.GetEmailAddressIndexForContact(String itemId, String routingAddress)
  at Microsoft.Exchange.Clients.Owa.Core.AutoCompleteCacheEntry..ctor(String displayName, String smtpAddress, String routingAddress, String alias, String routingType, AddressOrigin addressOrigin, Int32 recipientFlags, String itemId, EmailAddressIndex emailAddressIndex, Int16 usage, Int64 dateTimeTicks, Int16 sessionCount, Int16 sessionFlag)
  at Microsoft.Exchange.Clients.Owa.Core.AutoCompleteCacheEntry.ParseEntry(XmlReader reader)
  at Microsoft.Exchange.Clients.Owa.Core.RecipientCache.ParseRoot(XmlReader reader)
  at Microsoft.Exchange.Clients.Owa.Core.RecipientCache.Parse(Stream xmlStream)
  at Microsoft.Exchange.Clients.Owa.Core.RecipientCache.Load(UserConfiguration configuration, Stream xmlStream)
  at Microsoft.Exchange.Clients.Owa.Core.RecipientCache..ctor(UserContext userContext, String configurationName, Int16 cacheSize, UserConfiguration configuration, Stream xmlUserConfigurationStream)
  at Microsoft.Exchange.Clients.Owa.Core.AutoCompleteCache..ctor(UserContext userContext, UserConfiguration configuration, Stream xmlUserConfigurationStream)
  at Microsoft.Exchange.Clients.Owa.Core.AutoCompleteCache.FinishSession(UserContext userContext, UserConfiguration configuration, Stream xmlStream)
  at Microsoft.Exchange.Clients.Owa.Core.UserContext.Dispose(Boolean isDisposing)
  at Microsoft.Exchange.Clients.Owa.Core.UserContextManager.TerminateSession(UserContext userContext, CacheItemRemovedReason abandonedReason)
  at Microsoft.Exchange.Clients.Owa.Core.UserContextManager.UserContextRemovedCallback(String key, Object value, CacheItemRemovedReason reason)
  at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)
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