play video using adb shell command

[AC Question]

If I use the command
adb shell am start -a android.intent.action.VIEW -d "file:///mnt/sdcard/myvideo.mp4" -t "video/*"
The system prompts me to select a player..
I am trying to add the -n option to identify the player to use
The player is called: (used procrank and pm list packages -f to find the name)
android.rk.RockVideoPlayer
I appended
-n "android.rk.RockVideoPlayer"
to the earlier command, but get an "Error bad component name"

Can anyone explain what I am doing wrong and show the correct command?
Thanks