Differences in behaviour of DropDownBoxes between BW3.1 SP8 and SP12

Hy all

I have to systems with BW3.1

One is working with SP08 - the other with SP12

In both systems i have created a WAD/WEBTemplate with a single DropDownBox.

The code generated in the template looks as followed

When i now run the templates on the different systems i encounter different behaviour.

On SP08 i start the template like http://system.ch:1080/sap/bw/BEx?sap-language=EN&bsplanguage=EN&cmd=ldoc&TEMPLATE_ID=IIT_HS_DROPDOWN
Then the system brings back the dropdownbox with set to the first entry (All in my case).
So far everything is fine.
When i now select a different entry the template generates a link like http://system.ch:1080/sap/bw/BEx?ITEM=DROPDOWNBOX_1&FILTER_IOBJNM_1=3RC171ELJD2R9P5EH7DU92KFD&FILTER_COLLAPSE=&REQUEST_NO=1&PAGENO=1&FILTER_VALUE_1=3RC172OOP4P0DGE3G7RVXECQ1 and the selected entry is showed in the box.
This is the behaviour i expect. SP08 works correct on that.

On SP12 i start the template like http://system.ch:1080/sap/bw/BEx?sap-language=EN&bsplanguage=EN&cmd=ldoc&TEMPLATE_ID=IIT_HS_DROPDOWN
Then the system brings back the dropdownbox with set to the first entry (All in my case).
So far everything is fine.
When i now select a different entry the template generates a link like http://system.ch:1080/sap/bw/BEx and the dropdownbox will stay on the first entry.
I believe that the link need to look like the one in SP08.

When i look at the sourcecode in my browser is see that
SP08 generates code as followed

and
SP12 generates different code

My questions

Is this an error in SP12?

Do i have to set a parameter in BW/WAS to configure method="POST" or "GET"?

Or is this the new standard in SP12?

Thanks in advance