Rollershutters position range problem


I have problem mapping the position value from a rollershutter to a MQTT number.

There are two items defined, a Number and a Rollershutter:

Number NumberRoller  "" { channel="mqtt:topic:MqttBroker37:NumberRoller:numberRoller"  }
Rollershutter RollerRoller  "" { channel="mqtt:topic:MqttBroker37:RollerRoller:rollerroller"  }

With the corresponding identically configured topics in the MQTT bridge

Bridge mqtt:broker:MqttBroker37 [ host="localhost", secure=false ]
    Thing topic NumberRoller  {
            Type number : numberRoller "" [
    Thing topic RollerRoller  {
            Type number : rollerroller "" [

And a basic sitemap showing both items as the default view and a slider

sitemap site label="sitemap"{
    Frame label="Number" {
        Default item=NumberRoller
        Slider item=NumberRoller
    Frame label="Rollershutter" {
        Default item=RollerRoller
        Slider item=RollerRoller

Both sliders on the sitemap have a [0…100] range, setting the the corresponding item to values from 0 to 100, as expected. The default view of the item (Number and Rollershutter) show the expected values between 0 and 100.

When I look at the MQTT messages that are generated by using the sliders I get values from 0-100 from the Slider using the Number item and values from 0-1 (!) from the slider using the Rollershutter item.
In the other direction, when an MQTT message with values from 0-100 is received by the channel of the Number item it updates the item as expected. Sending a message with a number larger that 1 to the channel connected to the Rollershutter item result is an exception (IllegalArgumentException: Value must be between 0 and 100).

It seems to me somewhere along the line there is a transformation from the [0…100] range of the rollershutter to a [0…1] range used in MQTT and vice versa. This transformation is not present when using the number item.

How do I get rid of that transformation to get a [0…100] range in the MQTT state and command topic?

I know I can use a transformation pattern on the state topic, but AFAIK there is no such thing for the command topic. Also it seems a little weird that I have to transform back to the range the Rollershutter is using itself (at least for display).

Thanks a lot,

There have been changes to MQTT binding in connection with Rollershutters.
I wouldn’t put much effort into this until you have seen how the latest binding version behaves.

That sounds good. I assume you are speaking of work included in the upcoming 2.5 release? Is there any word on when that version is going to be released?