Error when editing Business Object for workflow

Hi,

we have a custom workflow and a business object with methods for this workflow.

Last week I wanted to add a new attribute to the business object and got the following error after selecting a transport for it.

"Internal Error: Structure TOJTB not existing"

Thats curious because the table is there and also the entries for our business object.

Error occurs after object was edited and a transport was selected.

Has anyone of you had this problem before or can assist?

There were no patches installed since the time where everything works fine.

Call BO in edit mode

Add attribute

Select transport

Error message

Thank you in advance.