Can't understand Inistialization steps after reset

Hi,
I can't completely figure out the initialization steps after power on for a Cortex-M3.

The exact issue I'm facing is discussed here :
www.keil.com/.../

But I can't figure it out where they say :

The area gets cleared by the scatter loader (executed between startup and entry to main).

the reset handler is as follows:

Reset_Handler   PROC
                EXPORT  Reset_Handler             [WEAK]
                IMPORT  __main
                LDR     R0, =__main
                BX      R0
                ENDP

I can't figure out where the scatter loader get's the chance to be executed!

I can't trace the initialization steps in reset handler. Can any one give me a link on the logic and nature of the initialization steps done before main