[Typo3-shop] Problem extending tt_products

[Simon Tuck]

Hi List,
I'm having a problem with extending tt_products: I need to add some fields which I then want to include via 
itemMarkerArrayFunc. The problem is that whatever fields I add via the extension kickstarter to the tt_products table they 
are not present in the TCA array in the front end. i.e. I can enter my additional fields in the backend, but if I dump the 
$GLOBALS['TCA']['tt_products'] array in the frontend it only contains the original tt_products TCA and none of the fields 
the kickstarter adds with t3lib_extMgm::addTCAcolumns and t3lib_extMgm::addToAllTCAtypes. This wouldn't realy be an issue, 
but it appears that tt_products uses the TCA array to build the query which gets the product information...
Just to be sure I've tested this with versions 2.3.1, 2.4.1 & 2.4.2 on clean T3 installations and I can reproduce the 
problem with each version.
So anyway, I was wondering if anyone else has had problems adding fields to tt_products or may be i'm just missing some 
special setting for tt_products or whatever...
Cheers,
Simon