No yasm support?

Hi

I have tried to run bootstrap.sh, but it does not recognize my yasm.
(MacOS X 10.5.5. + MacPort + yasm 0.7.0.2066)

Every entry for yasm support has gone under generic build... why?
I have 080820 snapshot src, and it has yasm entries under xvidcore/ 
build/generic/configure.in.
I also have read ChangeLog file, but it does not any information.

//

diff -u snippet btw 20080820 and 1.2.0 official following:

  dnl NASM version requirement
-minimum_nasm_patch_version=34
-minimum_nasm_minor_version=99
+minimum_nasm_minor_version=0
  minimum_nasm_major_version=2
  nasm_prog="nasm"
-yasm_prog="yasm"

:

     dnl
     dnl Checking for nasm compatible programs
-   dnl yasm is preferred over nasm, because... i can use it
-   dnl to profile assembly code ;-)
     dnl

etc...

Takashi Mochizuki