[Generate contours]Using fixed levels goes wrong

[meems@…]

We use the GDAL library in MapWindow (MW) and we found some inconsistancies with the gdal_contour function.
This function is wrapped in MapWindow in its Utils library and is used as:
u.GenerateContour(sGridFileName, sPolylinesFileName2, dInterval,
oGrid.Header.NodataValue, False, FixedLevels)
When I use this function in my VB6 application some grids create contourlines which are broken into several parts instead of being one long line.

First we tought it was a VB6 problem because when using the same grid and a VB.NET application the problem didn't occured.

But one of the other developers of MW has found out the same happens when using the gdal_contour command line tool.

So it looks like a genuine bug. Could someone look into it?

I've made also a bug report in the bugzilla of MW at:
http://bugs.mapwindow.org/show_bug.cgi?id=251
That report has not only more info but has also some sample data.

I hope someone can fix this.

With regards,
Paul