Its not a true problem, your door just isn't mapped yet -
you need to look up a tutorial on something called 'uv mapping'. Basically, you're going to end up moving all the uv coordinates into a reasonable shape. Hitting either Polygon Modeling -> Texturing -> Automap or Planarmap first will work best. Then you move the resulting map (and sewing them) as necessary. But, err... I'd reccommend trying a tutorial.
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