How to achieve an advanced table view header
===

I have a grouped `UITableView`. Now unlike the default table view header my header should be _next_ to the individual cells:

Standard:

    [Header Cell]
    [Item 1]
    [Item 2]

What I need 

    +-------+----------------+
    |       |  Item 1a       |
    |  h1   +----------------+
    |       |  Item 1b       |
    + - - - +----------------+
    |          Item 1c       |
    +------------------------+
    |       |  Item 2a       |
    |  h2   +----------------+
    |       |  Item 2b       |
    +------------------------+
    |       |  Item 3a       |
    |  h3   +----------------+
    |       |  -placeholder- |
    +-------+----------------+


Some remarks:

- Group H1 has three items
- Group H2 has two items
- Group H3 has just one item (I have to insert a placeholder cell so that the header cell can have the full height of two item-cells
- When the user scrolls the list then the header should be pushed upwards that the two header-cells don't overlap.

The challenge here is the height of the header cell:

- If I set the height to 0 and uncheck `clip subviews` then that header cell is shown but does not get pushed away at the correct position.
- If I set the height of the header cell to the visual height then there is an empty space of that height _across_ the whole width of the table which I don't want... 

**Update:** I just realized that apple uses such a list for the search (grouped by messages, mails, contacts, calenders etc.). So my question basically is how can I tweak `UITableView` in order to behave like the grouped search results... :-)


