CKEditor - An exception occurred in the client script. Error: undefined 

CKEditor - An exception occurred in the client script. Error: undefined 

  
I have several CKEditor's on a screen which are displayed and hidden by checking or unchecking a checkbox. When the CKEditor is initially hidden and displayed by checking the checkbox, it fine. However, if you uncheck (hide) and recheck the checkbox (redisplay), I will get error -- "An exception occurred in the client script.
Error: undefined", and the CKEditor no longer appears. This is a serious issue and I need to get this fixed. Does anyone know how to work around this problem?
Thanks!
Stumbled on this old post searching for "client script"...
As far as I've discovered, you can only use one CKEditor per web screen.
If you use more than one it will not work.
Solution: Redesign your web screen.