Simple fix; two lines needed to be switched so that the pointer
og.header points to something before it's used in ogg_page_pageno(&og);

Backtrace:
#0  oggbyte_init (b=0xbfbff71c, or=0x4, bs=0x0) at bytewise.c:90
#1  0x281c7557 in ogg_page_pageno (og=0xbfbff71c) at sync.c:68
#2  0x281c7b2b in _span_queued_page (os=0x8101100) at stream.c:296
#3  0x281c7ed1 in _packetout (os=0x8101100, op=0x8155160, adv=1)
    at stream.c:437
#4  0x281c814b in ogg_stream_packetout (os=0x8101100, op=0x8155160)
    at stream.c:511

svn path=/branches/libogg2-zerocopy/ogg/; revision=5656