"no_content" action done right?

I'm trying to implement a custom action with inline message feedback in Windchill 10.0 M030.

Here's my custom-actions.xml

{code}

[...]

<objecttype name="part" class="wt.part.WTPart">

  <action name="ps_send_to_plm">

  <command class="ext.xxx.connect.menu.SendTo" method="execute" windowType="no_content" />

  <resources>

  <label>Transfer to SAP</label>

  <tooltip>Triggers transfer to SAP</tooltip>

  <icon>xxx.gif</icon>

  </resources>

  </action>

  </objecttype>

[...]

{code}

The menu entry is visible in the "Actions" menu for WTParts but when I click on it a inline message appears saying:

"CONFIRMATION: Successful copy

  Hello World object(s) copied to the clipboard"

The "Hello Worlds" comes from my ps_send_to_plm.jsp and I figured out that the rest is coming from a JS method showCBMess which seems to be a method handling clipboard operations (e.g. copy).

What am I missing here?