I assume you've seen the openquery documentation here (which indicates the same restriction back to 2000)
So you know can still do the following?
EXEC [linked_server].[db].[schema].[xProc]
You can also create a local synonym for that proc if your complaint about making linked server calls directly was about having to use the four-part name.
Or maybe I'm missing the difficult part...
Dan Guzman - Not the MVP (7/22/2010)
All questions have to be prefaced by Server version and 'according to MS Docs' or 'my own personal opinion based on how much detail I felt like digging into at the time.'