Options of XviD-Codec in combination with MPlayer/MEncoder?

Hello!

I would like to use MEncoder to create my XviD videos. Therefor there seem 
to be two choices: lavc (libavcodec integrated xvid) and "native 
xvid" (my expression, don't know if it is suitable), which means usage of 
the xvidcore library You can download as source code from www.xvid.org.

MEncoder is the program of my choice. Lavc/libavcodec isn't. Therefor I 
have to - or should - use something like:
# mencoder -ovc <codec> -<codec>opts <option1[=value],option2,...>
In my case:
# mencoder -ovc xvid -xvidopts ....

1) Is this true? Is it "-xvidopts" or is it "-xvidencopts"? Any ideas/
experiences?
2) What are the option names I can specify as "option1=xxx,...."? Where 
can I find a list of the apropriate names, commands and values? I looked 
in the XviD core source tar ball directory. Neither in XviD 0.9.2 nor in 
XviD 1.0.0 beta there is any docs to this. It is advice etc. for 
programmers and co. which I don't belong to. ;)

Any ideas whether this is the right path I'm walking on?

Happy about suggestions and pointing out for proper documentation,
greetings, Stephen.