Duration of the converted .mov video is lower than the original video

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Record a video using the screen recorder (minimum 30s long)
2. Play the video using the screen player => video duration seems OK
3. Convert the video to .mov using the recording converter => the converted 
video duration is lower than the original one (period between frames seems 
lower in the .mov file)

What is the expected output? What do you see instead?
After a conversion to .mov, both converted video and original video should have 
the same duration.

What version of the product are you using? On what operating system?
- Screen recorder 2.2
- Screen player 2.2
- Recording converter 1.1

Please provide any additional information below.
JMF 2.1.1e (Windows package)

Original issue reported on code.google.com by [email protected] on 14 Jul 2010 at 9:59