Resourcegroup problem[Solved]

Hello,

I have a resource group defined in resources.cfg.
[gui]
FileSystem=../media/gameproject/gui

The group is called 'gui' (notice only lower cases).

I define the resource groups in ogre startup.

Im initializing MyGUI with:
mGui->initialise(Ogre::Root::getSingletonPtr()->getAutoCreatedWindow(), "core.xml", "gui");

At this point I receive an exception.
OGRE EXCEPTION(5:ItemIdentityException): Cannot locate a resource group called 'Gui' in ResourceGroupManager::findResourceFileInfo at f:\codingextra\ogre\shoggoth_vc9\ogre\ogremain\src\ogreresourcegroupmanager.cpp

Notice the uppercase 'G'. Where does that come from?
The last couple of lines in mygui log:
[...]
20:28:37 | General | Info | DelegateManager successfully initialized | c:\development\sdk\mygui\myguiengine\src\mygui_delegatemanager.cpp | 21
20:28:37 | General | Info | * Initialise: LanguageManager | c:\development\sdk\mygui\myguiengine\src\mygui_languagemanager.cpp | 21
20:28:37 | General | Info | LanguageManager successfully initialized | c:\development\sdk\mygui\myguiengine\src\mygui_languagemanager.cpp | 28
20:28:37 | General | Info | Load ini file 'core.lang' from resource group : Gui | c:\development\sdk\mygui\myguiengine\src\mygui_resourcemanager.cpp | 155


I can't find any place in my code where I've literally written 'Gui'...only 'gui'.

Of course when I was done posting this report I looked in core.xml and I had written
<List file="core.language" group="Gui"/>