[TYPO3-dev] TYPO3 BE extensions: sub and main modules and registerModule()

[Michael Schams]

Hi

I struggle to solve a problem with two extensions and their visual 
appearance in the backend of TYPO3 CMS 6.2:

I've got two extensions, which should be listed as sub-modules of a new 
main module in the left column. Somethink like that (where the "HELP" 
section comes from the core of course):

[...]
HELP
- About TYPO3 CMS
- TYPO3 Manual
- About Modules

MY MAIN MODULE
- My Extension One
- My Extension Two

The point is, that both extensions ("My Extension One" and "My Extension 
Two") are independent from each other. You can install either one of 
them or both - and they should both appear under "MY MAIN MODULE".

How should the method registerModule() in ext_tables.php look like?
According to the API [1] documentation:

registerModule(
   $extensionName,
   $mainModuleName = '',
   $subModuleName = '',
   $position = '',
   array $controllerActions = array(),
   array $moduleConfiguration = array()
);

Whatever I try, it does not work... it throws an exception or the main 
module name appears twice when I install both extensions:

MY MAIN MODULE
- My Extension One

MY MAIN MODULE
- My Extension Two

I have assumed, both extensions should include registerModule() twice? 
First for defining the main module and empty arrays controllerActions 
and moduleConfiguration - second for the sub module(s).

Could anyone point me in the right direction or provide me with an 
example how to set this up correctly?


Thanks
Michael

[1] 
http://typo3.org/api/typo3cms/class_t_y_p_o3_1_1_c_m_s_1_1_extbase_1_1_utility_1_1_extension_utility.html