Sox, compiled to encode mp3, still won't

["Patrick Wiseman" <pwiseman@gmail.com>]

Hello:

I have repackaged sox to encode mp3, and, as it's building it reports
that I did that properly:

MAD MP3 reader.................... yes
id3tag library.................... yes
LAME MP3 writer................... yes

But when I try to encode to mp3, I still get:

 Can't open output file `test.mp3': SoX was compiled without MP3
encoding support

Any thoughts about what I've missed?  And, yes, I have installed it!

Patrick