Maya 2011 Vector Blur
Things are a bit different now when rendering vector blur. Now Maya has incorporated it into render passes. You no longer need the LM2DV shader.
Render out 32 bit EXR with the blur embedded into the pass and break it out into your comp package. This is how to do it with Maya's "composite" package.
1. Separate your FG and BG into render layers.
2. For each layer needing vectors, go into your passes tab in render settings and
add a BEAUTY and a mv2Dtoxik (2DmotionVector) pass.
3. In your quality tab make sure your framebuffer is RGBA 4x32bit instead of the default 8.
4. Image format - openEXR
COMPOSITE - See image for nodes used and also use this dude's video http://www.youtube.com/watch?v=GMKvhKf22r8