[Libreoffice] Help with moving misplaced options from ScDocOptions to ScAppOptions

Hi devs,
I took on the relative straight-forward task to move some misplaced
options in calc from ScDocOptions to ScAppOptions. The rational behind
this move, see:
http://lists.freedesktop.org/archives/libreoffice/2011-May/013087.html

Simple as this task might seem (it's is mostly a matter of copy&paste)
I still have run into troubles that I can't figure out. In
tpcompatibility.cxx we have the following line:

 const ScTpCalcItem& rItem = static_cast<const ScTpCalcItem&>(
         rCoreAttrs.Get(GetWhich(SID_SCDOCOPTIONS)));

Ref::
http://opengrok.libreoffice.org/xref/calc/sc/source/ui/optdlg/tpcompatibility.cxx#48

I'm no quite sure what this line actually does. It seems to identify
the ScDocOption class and bind a pointer to this class to a
ScTpCalcItem.
Unfortunately for me there is no corresponding slot-ID to
SID_SCDOCOPTIONS for the ScAppOptions class, otherwise I could just
changed that and be done.

The question is now how to implement some corresponding functionality
here for ScAppOptions.

As I understand the overall purpose you what to create two pointers to
copies of the option set, manipulate one set, compare them and then
store the modified set to file.

Help on this is appreciated.

TIA

/Albert

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