Tom said from the sound of my post that I must be in the trunk also! It was worse.....most of my tools were in the trunk that day. When talking to the oldest parts guy at the mercedes dealer I was reminded that the key in the trunk tumbler should override the vacuum element in all circumstances. Of course I had proof in front of me that this was not so! But it gave me the reinforcement to do what many suggested and just keep jiggling and prying. It eventually sprung! I found that the tiny rod which connects the vacuum element to the tumbler is very sensitive in its adjustment distance. A little too much in the wrong direction and the plunger in the trunk lock still pushes in but the latch does not release. This is easy to watch and adjust WHILE THE TRUNK IS STILL OPEN. Thanks for the responses, this forum is a great backup.