[OSM-newbies] Mapnik - weird rendering for disused railway.

[Dave F.]

Hi

Could you have a look at this please?

http://osm.org/go/eukiM1Dp6-

I've mapped a stretch of disused railway line 'Bristol and North 
Somerset Railway'
As you can see south of the B3110 it only displays a short length of the 
bridge section even though it's a joined way.

I've tested the status :

Tile is clean. Last rendered at Sun Oct 25 11:44:25 2009

But if you check, I last updated it back at the beginning of August.

It appears to fail at a few zoomfactors, but not all.

Any ideas as to what's wrong & a solution?

Cheers
Dave F.