Thanks for that TD03-5.
I actually found the proper dreambox scripts in the build environemnt for OpenPli and they also have a wiki on their website (under recent changes, which is not obvious to find; look in the top tool bar).
The dreambox scripts have a bug: If you specify a destination the IPKG build fails, the only way that works is "build-ipkg <package directory>" which will create the .ipk in your current directory.
Also: for anyone that wants to build a plugin .ipk, the wiki shows "architecture: mipsel" in the control file, it should be "architecture: all" for python written plugins as they are not processor dependent. However, remember to specify the depends: enigma2 so the plugin cannot be installed on enigma1 boxes.
If you look on the OpenPli website, I have a post there that clarifies how to build an .ipk, showing the required directory structure and sample control file(change "architecture: MIPS" to "architecture: all" in the example.
NOTE. The dreambox ipkg creation program is NOT called mkipkg, it is called build-ipkg; this is why it was such a pain finding it in the build environment of OpenPli. The OpenPli scripts work fine on Ubuntu and on the actual dreambox itself.