We are using Portal 6.1.0.1 with JSR268 Inter-Portlet Communication between 2 portlets on different pages (the 1st portlet is a list of items, and the 2nd is the detail of the item).
Most of the time, we are able to setEvent correctly to switch between the 2 portlets.

However, every now and then, we get the error as attached when we press an item in the list on the 1st portlet.
If this happens, this item will always get this error even when we open a new browser or reboot the server.

Any ideas?