From Forum Nokia Wiki

ID	KIC000487	Creation date	November 30, 2006
Platform	S60 1st Edition, S60 2nd Edition, S60 3rd Edition	Devices
Category		Subcategory

Keywords (APIs, classes, methods, functions):

Description

The layout attribute defined in the MMS SMIL file is ignored by Nokia devices (they use their own layout). This is done because the devices receive all kinds of data from other devices, and otherwise the content would not be seen properly.
This can be prevented by using 3GPP SMIL which is much richer than the MMS SMIL profile. The MMS SMIL is a subset of 3GPP SMIL and thus included in support for the 3GPP SMIL.