the "header" is the module Title, there are several reciepts in these forums, how to set it dynamically and even the core contains a few examples (like user login).

The header text you are referring to is displayed by the TITLE Skin element.

In the TITLE skin element page load event the property

Me.ModuleConfiguration.ModuleTitle

is queried for its current value - this value is used to then display the title text.

AS a result if you change the value in your modules PAGE_INIT event like this

Me.ModuleConfiguration.ModuleTitle  = " MY NEW TITLE TEXT"

The MY NEW TITLE TEXT will be displayed as the container title.

NOTE - you can ONLY do this int he PAGE_INIT - and not in the PAGE_LOAD - since your modules
PAGE_LOAD fires AFTER the TITLE PAGE_LOAD,

Westa