Missing grid lines

We've had an ongoing issue with missing vertical grid lines in our tree stores. Finally was able to find time to isolate the issue. If you use set_visible on various tree view columns, to hide certains parts of the data, and then set grid lines for both or vertical on that view, gtk will drop off a corresponding grid line for every previous column that is hidden. We have a lot of hidden columns, for various reasons, so we end up with only a few columns on the left having grids and all the rest missing. Haven't see any issue with the horizontal grids, probably because we don't attempt to hide any rows, just columns. Has anybody seen this? Any possible solutions, other than having to rework thousands of lines of code to switch all the hidden columns to the end of the array? (The latter is not an option at the moment). thanks, Madeleine D.