Use of host macros

[pcamelio]

HI folks,

I am trying to use host macro unsuccessfully

Host template _DFS
Macro : {$DFS} => WDS

Item
nbfiles[{$DFS}]

Create two hosts linked to the template _DFS
_DFS_WDS_MYHOSTNAME
_DFS_KERIO_OTHERHOST + macro hostname {$DFS} => KERIO

every 15' I run a task and send these values using zabbix sender

_DFS_WDS_MYHOSTNAME:nbfiles[WDS] 0
_DFS_KERIO_OTHERHOST:nbfiles[KERIO] 0

but nothing happens

If I send
_DFS_WDS_MYHOSTNAME:nbfiles[{$DFS}] 0
_DFS_KERIO_OTHERHOST:nbfiles[{$DFS}] 0

item are updated

If the items is not defined in a template, the macro is working ...