legacy api with 1.1 library question

Hi All,

If an application is written against the legacy API (theora.h), but compiled 
and run on a system with the 1.1 libraries and headers installed, and then at 
runtime sets bitrate=0, will the theora 1.1 VBR be activated in the encoder?

How can one verify that an existing ogg/theora stream is using VBR?

Alternatively, does anyone have a guide to porting a program from the
legacy API to the 1.1 API?

Thanks,
David