Scale bar in print preview

[jonathan-wcc]

(bug?)
I think this is a GeoExt issue but may be wrong (feel free to close it).
See this issue - http://code.google.com/p/geoext-viewer/issues/detail?id=167

The print preview scale bar doesn't use the projection that's been declared elsewhere. Other scale bars are all fine (the main map one and the MapFish printed output).

To work around it I have to explicitly declare the proj4js EPSG:

Proj4js.defs["EPSG:27700"] = "+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs ";
EPSG27700 = new OpenLayers.Projection( "EPSG:27700" );