As I haven't found it anywhere else, I'll drop a little note here.
To get the hotkeys working under BT4 on a EeePC 701, just install the latest eeepc-acpi-utilities deb from Browse EeePC ACPI Utilities Files on SourceForge.net , maybe you also have to add p4-clockmod and eeepc-laptop to /etc/modules if the deb did not already loads them.

ciao