Here's a little 2 line script that I usually use with mencoder that
works for me.
mencoder $1.avi -sub $1.srt -ovc lavc -lavcopts \
vcodec=mpeg4:keyint=100:vbitrate=1000:vb_strategy=1:vpass=1 -oac copy
mencoder $1.avi -sub $1.srt -ovc lavc -lavcopts \
vcodec=mpeg4:keyint=100:vbitrate=1000:vb_strategy=1:vpass=2 -oac copy
Just tried something similar using -ovc lavc -lavcopts vcodec=mpeg4 (etc.)
and the player said codec unsupported. Did you do any firmware upgrade or
something?
Would it be too much to ask to encode with mencoder a chapter, say, from a
dvd, test it on your player then post the file somewhere where I can
download, to try it on my player? Something a few Mb should suffice. I
can't let this go until I sort it out. I can't tell right now if it's the
player or mencoder.