Comment 10 for bug 1068642

Hi, I know this is much later, but some of us on the Lubuntu dev mailing list are working on tracking down this issue. It seems that many programs using an xpm format for the icon have this issue.
There isn't a clear fix for this yet, but if you want a work-around you can use imagemagick to convert the image.
usually this icon is located in /usr/share/pixmaps
So from a terminal
convert <whatever the icon name is> -scale 22x22 <whatever the icon name is>

Most of the packages affected are not maintained in Debian anymore.
The proper fix would be to edit the rules file and desktop file in the source to make a png image the icon image with a relative name
Desktop file snippets:
Icon="ProgramName"
instead of
Icon="/usr/share/pixmaps/ProgramName.xpm"