Probably going to need more information about how mplayer is not being accessed correctly.
CGI uses the shell environment to pass web information to a program... so maybe this is messing up mplayer. You'll need to augment or wrap your partners program in order to give you more information about what's failing (e.g. wrap the call to mplayer in a try/except use the traceback module to format a traceback if your CGI server is swallowing it). -- http://mail.python.org/mailman/listinfo/python-list
