The original DV file is avi 5.5GB (lets say A.avi) .
I isolate a small portion of 5 secs using AviDemux (lets say B.avi) .
B.avi is interlaced again .
For some peculiar reason 6.21 succeeded to export deinterlaced both A.avi and B.avi ,
Using 7.24 export file A.avi is interlaced but B.avi is OK deinterlaced .
The problem is I can't sent A.avi . The small sample B.avi is succsesfully exported using 7.24 .