SVCD res is not interlaced/VCD res is interlaced

[Kb_cruncher]

I am working on a PAL Interlaced DVD source.When i encode at SVCD resolution there is no visible interlacing but when i encode with VCD/CVD resolutions the encode always has visible interlacing.This also happens on non-interlaced(progressive)sources.i have tryed everything i know to fix it without any results.Any help would be appreciated.

thanks
Kb_cruncher