You could create a new report.gif and upload it and then changed the CSS for ".postbitlegacy .postfoot .textcontrols a.report, .postbit .postfoot .textcontrols a.report" and ".postbitlegacy .postfoot .textcontrols a.report:hover, .postbit .postfoot .textcontrols a.report:hover" to point to your new image.
Lynne,
Thanks very much- that is what I will do. I did notice that there was an image named report-40b-hover.png and report-40b.png in the images/buttons directory. I presume those are the images in question. If I simply replace the images and use the same names, I presume I won't have to change the addresses in the templates.