OGR: NULL attribute value not written properly in ESRI Shapefile

[amagnum2@…]

I am trying to merge several shp files with ogr2ogr and I found that when ogr 
writes the output it does not handle the NULL values properly. Instead garbage 
is written.
Under GML output, there are no issues with NULL - the property is simply 
excluded from the feature so I am guessing the issue is with ESRI output.
I found that regardless of the -append flag of ogr2ogr this problem exists.

I am attaching a sample SHP file. The command line I use for ogr2ogr:
ogr2ogr -f "ESRI Shapefile" myshp.shp  tgr20209lkA.shp tgr20209lkA

When opening the DBF file in Excel, you can see the grabage data in some of 
the rows.

[amagnum2@…]

ESRI shapefile with nulls

[warmerdam]

Ariel,

Can you provide your "myshp.shp" and the source "tgr20209lkA.shp"? 

I tried translating a dataset to shape format that has null attributes
and displayed it in Excel and it seemed fine.  I suspect the issue is 
specific to particular field types, or possibly relates to your source
dataset. 

[amagnum2@…]

output shp file

[amagnum2@…]

(In reply to comment #2)
> Ariel,
> Can you provide your "myshp.shp" and the source "tgr20209lkA.shp"? 
> I tried translating a dataset to shape format that has null attributes
> and displayed it in Excel and it seemed fine.  I suspect the issue is 
> specific to particular field types, or possibly relates to your source
> dataset. 


The input shp file is already attached to the bug as "ESRI shapefile with 
nulls"
I have now attached the output as "output shp file".


Ariel

[amagnum2@…]

Checked with latest, bug is fixed.