vorbis_encode_setup_managed guesses bitrate after calculating quality factor

Here's the patch:

=========================================================
==========
RCS file: /usr/local/cvsroot/vorbis/lib/vorbisenc.c,v
retrieving revision 1.33
diff -c -r1.33 vorbisenc.c
*** vorbisenc.c 2001/12/23 11:53:53     1.33
--- vorbisenc.c 2002/01/03 08:51:44
***************
*** 914,936 ****
                                long nominal_bitrate,
                                long min_bitrate){
  
!   double tnominal=nominal_bitrate;
!   double approx_vbr=approx_bitrate_to_vbr(channels,(channels==2), 
!                                         (float)nominal_bitrate,rate);
    int ret=0;
!   if(approx_vbr<0)return(OV_EIMPL);
! 
!   if(nominal_bitrate<=0.){
!     if(max_bitrate>0.){
!       nominal_bitrate=max_bitrate*.875;
      }else{
!       if(min_bitrate>0.){
!       nominal_bitrate=min_bitrate;
        }else{
        return(OV_EINVAL);
        }
      }
    }
  
    ret=vorbis_encode_setup_vbr(vi,channels,rate,approx_vbr);
    if(ret){
--- 914,938 ----
                                long nominal_bitrate,
                                long min_bitrate){
  
!   float tnominal=nominal_bitrate;
!   double approx_vbr;
    int ret=0;
!   
!   if(nominal_bitrate<=0){
!     if(max_bitrate>0){
!       tnominal=(float)max_bitrate*.875f;
      }else{
!       if(min_bitrate>0){
!       tnominal=(float)min_bitrate;
        }else{
        return(OV_EINVAL);
        }
      }
    }
+ 
+   approx_vbr=approx_bitrate_to_vbr(channels,(channels==2), 
+                                         (float)tnominal,rate);
+   if(approx_vbr<0)return(OV_EIMPL);
  
    ret=vorbis_encode_setup_vbr(vi,channels,rate,approx_vbr);
    if(ret){