Failed to get alias mappers sub context in the Portal Registry

hello all,

i see many messages on my log files.

can any one please tell me what they mean ?

thanks

#1.5#0013216BB88B0067000000530000427000040BB93E6EA5A0#1138790151245#com.sap.portal.ivs.semantic.systemLandscape#sap.com/irj#com.sap.portal.ivs.semantic.systemLandscape#DepotTa#1626####83e43fd0930e11da90a90013216bb88b#SAPEngine_Application_Thread[impl:3]_11##0#0#Error#1#/System/Server#Java###Failed to get alias mappers sub context in the Portal Registry##