DV rack QT - is there a problem

[HVX2006]

When i import or drop on the time line my 1080/25p DV rack footage FCP shows a message that says something like- "These files are not optimized for FCP try to recapture....."(not quite sure of the wording) never than less FCP lets me work with these files fine. Is this just a standard warning or do i need to change anything? I am running FCP 5.1.2.

Can someone clarify. Thank you

[HVX2006]

Actually what happens is that a window called "Media performance warning" pops up.

It says-

The following media files are not optimized for FCP
It is highly recommended that you either recapture media or use media manager to create new copies of the files to improve their performance for multi-stream playback.


Below it lists the clips.


what does this mean?