This all seems impossible, I hope I can keep it short so that people will not lose their pacience before the end...

This morning one of the developers in our department made a change to a form class, by adding a button, saved the class and cleaned up the class library.
On his computer everything is OK, you create a new form of that class, it has the new button. Or, you open an existing form of that class, the button shows up.

On all other development computers, what is seen is the old class - no button on the form when opening an existing form or creating a new one. We tried first CLEAR ALL, then Quit VFP, even shut down the computer, it will still find the old class!!

If we quit VFP on the computer were the class was modified, and go back in, even that computer will only see the old class - no button.

On any computer, if we open the class itself with modify class, class browser, or from a project, it will show up with the new button, and after that, opening any existing form, or creating a new form will pick up the new class.
As soon as you quit VFP, and go back in, the old class is back, until you open the class for modifying...

So, if we saved and packed the .vcx, where is VFP finding the old definition of the class?

Some background:
The directory structure is as follows:

\\apps\app1
      \app2
      .....
      \classes\ (all class libs are here; \classes is NEVER in the VFP path)
      .....

Any help will be greatly apreciated.