Informational event log entry

I have one particular AOS server that is getting informational entries in the event logs does anyone know what they mean this is the entry “AxContextInitializer::BeforeInvoke: No session available.” I have checked the server and it does not look to busy but I think that there maybe to many sessions on the AOS server already, does this sound right and should I be worried about this entry. thanks in advance guys.

First of all, which version of AX are you talking about? Please always attach a tag with the version when creating a new thread.
Also, please give us much information about the problem as possible. For example, how often does it happen? What are other information in the event log, such as the source of the event?