Did some testing, and it seems that it has to be
#itemXlabel:ID
Meaning that you would have to have a ID and not a typed name.
There are two ways of working around this, as I see it:
1. Create ID's in language xml's (haven't tested yet, but will do. I do not see any reason why it should not work)
2. Search and replace all #itemXlabel with your preferred label.
(I'd go for 1)
#itemXlabel:ID
Meaning that you would have to have a ID and not a typed name.
There are two ways of working around this, as I see it:
1. Create ID's in language xml's (haven't tested yet, but will do. I do not see any reason why it should not work)
2. Search and replace all #itemXlabel with your preferred label.
(I'd go for 1)