[TYPO3] Strange record labels after itemsProcFunc in TCA

[Simon Tuck]

Hi Peter,
> 
> your functions points to a record that doesn't exist.
> [12!] => there is no record with uid=12 in DB

I guess that's the correct answer to my question. The problem is that it doesn't explain what I am seeing in the BE list view.
The function I'm using changes the key for the table relation. so in the examples below:

record from table#1
123456789, [12!], [567623767!]

record from table#2
123456789, 12, Test

123456789, 12 &  567623767 are keys for table relations. they use the same function to change the key field. there are no uids for any of these 
values (obviously as the uid is not the table relation key). If the bracket/exclamation denotes a missing uid then all the values should be 
bracketed. but they're not. what's more in table #1 the 12 appears bracketed, while in table 2 the exact same TCA appears ok.

is this a bug? does somebody know which class/method is responsible for this magic - I'd like to have a closer look...
Cheers
Simon