Command Line render freezes


I have a document that renders a sequence setup in the Video Sequence Editor:
video file from disk(no audio), then a 3d scene then, then another video, then another tiny 3d scene.

I have a basic script that just starts the render:

import Blender
from Blender import *

scn = Scene.Get('video_seq')
context = scn.getRenderingContext()

I’m using Blender 2.49 (build 22966) on OSX 10.5.8

On my machine, everything is ok.

On another machine that runs OSX 10.6 the
rendering freezes in the middle of the second video.

I tried to render just the first video and first 3d scene and it worked.
Then tried to render just the second video and the second 3d scene in isolation
and that worked.

When all scenes are sequences, Blender freezes.

Increasing the Memory Cache didn’t seem to change anything.

Has anyone encountered something similar ? Any hints ?