Joining wmv files

ex.1
mplayer\mencoder.exe -oac copy -ovc copy -of lavf -lavfopts format=wmv u:\t\a_1.wmv u:\t\a_2.wmv -o aa.wmv

ex.2
mencoder -oac copy -ovc copy -of lavf -lavfopts format=asf myfile.wmv.001 myfile.wmv.002 -o myfile.wmv