Windows Vista Subtitles in WMP 12 with mpeg4 film

Hello:
I have a laptop running Windows 7 Home Premium (64Bits).
When i need to reproduce subtitles with an MPEG4 Type film WMP does not reproduce the subtitle.
I installed K-Lite Full 5.7.5 and with Media Player Classic HomeCinema the subtitles are displayed.
If the film is in AVI Type everything run well.
Can someone help me?
Best Regards
Curious

Enable Subtitles in Windows 7 Media Player 12

OR

use alternative players like WMC, Media Player Classic, VLC, GOM, etc.