Database connection problems - table not filtering

I'm running ArcGIS10.1 on Win7 64bit with Oracle 11g and I'm having trouble with database table connections in Oracle. In Modelbuilder I use the MakeTableView tool and apply a filter expression so that I only get the 5 records I want from a table. When I run the CopyRows tool after that, I get all 150,000 records copied over. Arcpy does the same.

When running the same procedure on another machine with Arc10.0 it works fine and I get only the 5 records...
Any ideas what the problem might be?
Thanks,

Frank