this problem requires a 17 mm spanner and 5 minutes of your time. Crawl under the van directly below the gear stick, you will find a plastic box with 4 or 5 spring clips on it, remove the lid. There is a bolt that holds the gear stick to the forward/back gear selector mechanism, simply tighten this bolt using said 17mm spanner, replace lid, happy motoring!
campo, February 2009