DVBs and DVBs2 are using different modulation. The content can be either MPEG-2 or MPEG-4 video or any data. DVBs use QPSK modulation and DVBs2 uses 8PSK or 16APSK or even 32APSK. You can't use DVB-S receiver for DVB-S2 because the difference in modulatio.
So you can't use DVB-S MPEG4 receiver for receiving DVB-S2 MPEG4 channels.
http://en.wikipedia.org/wiki/DVBS2 for more info