Security messages while opening Office 2003 documentsLink

I receive security messages when opening Word or Excel documents under office 2003. Is there another possibilityto change this than lowering the security level?
Unfortunately, there is no so elegant solution for Office 2003 as for example for Office in 2007 with the trusted locations. Nevertheless, it is possible to stop the query in general for ActiveX controls in Office 2003, by inserting a key into the Windows Registry. Please note, that this solution is not only for our control but for all ActiveX controls. You would receive this warning also no longer with foreign controls!

Der Registry Eintrag lautet:

If you liked to carry out the change, please note that the update of the Registry always has a certain danger. We recommend you, to perform a data abckup before the intervention in the Registry.