[Seaside] registerObjectForBacktracking, submit and execute block

[Andreas Nilsson]

I'm trying to build an edit form with a table displaying items, a 
checkbox for each item and a link to delete all checked items.
In my form i have two collections, one to keep all items and another 
one to keep the selection.
It all worked flawlessly until i decided to register the collections 
for backtracking, now nothing happens when i delete items.
The problem as I see it is that the snapshot is taken when the form 
submits, before the block is executed that removes the checked items.

Current behaviour:
1)	Submit to update selection
2)  	Take snapshot for backtracking
3) 	Execute block removing checked items

Correct behaviour:
1)	Submit to update selection
2)	Execute block removing checked items
3)	Take snapshot for backtracking

It feels like Seaside somehow has to capture the fact that i'm 
submitting and executing a block at the same time and run the block 
before taking the snapshot.

/Adde