Firefox can not open an streaming link from a website

[Tenoch]

Binary package hint: firefox-3.5

On the same computer i have Firefox 3.0.15 and this version works fine when trying to see the stream of the following website http://www.ntrzacatecas.com.mx/ there is a picture on the report that shows where you need to ciick to see the video. So the problem is that when i click on the link to see the video using firefox 3.5.4 mplayer does not open, not allowing me to see the video stream.