Grady Sutton and Strother Martin
These two cameos are notable.
There was no mistaking Grady Sutton as the reporter who wanted to set up an interview with Vicki Lester. (You may remember Grady Sutton from The Bank Dick as Og Ogilby.)
I wasn't sure about Strother Martin as the delivery boy (who says "sign here, Mr. Lester" to Norman Maine) but the IMDB cast list confirms it.
What they had there was failure to communicate.
Janet! Donkeys!