Runtime trace error logs - BW datasource

When I use BW as a datasource in Design Studio and when I activate the runtime trace, I get the following warning messages in the error log.

!ENTRY com.sap.ip.bi.zen 2 0 2013-05-29 23:37:47.333
!MESSAGE Recording RSTT trace with ID "LOC_000031"...

!ENTRY com.sap.ip.bi.zen 2 0 2013-05-29 23:37:47.336
!MESSAGE ABAP User Name: UNKNOWN

!ENTRY com.sap.ip.bi.zen 2 0 2013-05-29 23:37:48.464
!MESSAGE Recording RSTT trace with ID "LOC_000031"...

!ENTRY com.sap.ip.bi.zen 2 0 2013-05-29 23:37:48.466
!MESSAGE ABAP User Name: UNKNOWN

Why do I see a Unknown ABAP username even though I use a valid BW user for the datasource?

My application runs fine locally.

Anyone notice these messages with trace activated? Just Curious.

Thanks,

Murali