2.49 Secuencer Bug?

Video sequence editor with a strip of render PNG images
Output of secuence to Node (RGB curves color correction)

Not render

It´s a bug?

Not sure what this means but I have had PNG strip have its frames re-ordered in sequencer timeline. I had to find at what frame the change occured and move them to a seperate folder then ADD them as a seperate strip. This was in 2.49b as well (win 32bit).