Problem with exporting FLA file with UI components

I am having a problem exporting flash file containing UI components.
When I export my FLA as an image (Jpg, Png etc) the UI componets [color=red]ju[/color][color=red]st disappears[/color]. The rest of movie clips which are drawn in FLA authoring mode are retained.

Any specific reason why this is happening? Am I missing any step while exporting.