Exchange 2010 How to set-AdServerSettings -ViewEntireForest $true permenantly

 I have an issue where the exchange console cannot update objects that exist in a child domain.

when i run set-AdServerSettings -ViewEntireForest $true  , I can run the requered commands via the command line , i would like to make this a permanent setting on exchange . So it does so by default via command line and the management console.

Thanks