diff -Naurp rrdtool-1.2.99908020600/src/rrd_graph.c rrdtool-1.2.99908020600.fix/src/rrd_graph.c
--- rrdtool-1.2.99908020600/src/rrd_graph.c	2008-02-05 19:14:25.000000000 -0500
+++ rrdtool-1.2.99908020600.fix/src/rrd_graph.c	2008-04-30 21:12:13.000000000 -0400
@@ -3345,34 +3345,36 @@ int graph_paint(
         switch (im->gdes[i].gf) {
         case GF_HRULE:
             if (im->gdes[i].yrule >= im->minval
-                && im->gdes[i].yrule <= im->maxval)
-                cairo_save(im->cr);
-            if (im->gdes[i].dash) {
-                cairo_set_dash(im->cr, im->gdes[i].p_dashes,
-                               im->gdes[i].ndash, im->gdes[i].offset);
-            }
-            gfx_line(im,
-                     im->xorigin, ytr(im, im->gdes[i].yrule),
-                     im->xorigin + im->xsize, ytr(im,
-                                                  im->gdes[i].yrule),
-                     1.0, im->gdes[i].col);
-            cairo_stroke(im->cr);
-            cairo_restore(im->cr);
+                && im->gdes[i].yrule <= im->maxval) {
+                    cairo_save(im->cr);
+                if (im->gdes[i].dash) {
+                    cairo_set_dash(im->cr, im->gdes[i].p_dashes,
+                                   im->gdes[i].ndash, im->gdes[i].offset);
+                }
+                gfx_line(im,
+                         im->xorigin, ytr(im, im->gdes[i].yrule),
+                         im->xorigin + im->xsize, ytr(im,
+                                                      im->gdes[i].yrule),
+                         1.0, im->gdes[i].col);
+                cairo_stroke(im->cr);
+                cairo_restore(im->cr);
+            }
             break;
         case GF_VRULE:
             if (im->gdes[i].xrule >= im->start
-                && im->gdes[i].xrule <= im->end)
-                cairo_save(im->cr);
-            if (im->gdes[i].dash) {
-                cairo_set_dash(im->cr, im->gdes[i].p_dashes,
-                               im->gdes[i].ndash, im->gdes[i].offset);
-            }
-            gfx_line(im,
-                     xtr(im, im->gdes[i].xrule), im->yorigin,
-                     xtr(im, im->gdes[i].xrule),
-                     im->yorigin - im->ysize, 1.0, im->gdes[i].col);
-            cairo_stroke(im->cr);
-            cairo_restore(im->cr);
+                && im->gdes[i].xrule <= im->end) {
+                    cairo_save(im->cr);
+                if (im->gdes[i].dash) {
+                    cairo_set_dash(im->cr, im->gdes[i].p_dashes,
+                                   im->gdes[i].ndash, im->gdes[i].offset);
+                }
+                gfx_line(im,
+                         xtr(im, im->gdes[i].xrule), im->yorigin,
+                         xtr(im, im->gdes[i].xrule),
+                         im->yorigin - im->ysize, 1.0, im->gdes[i].col);
+                cairo_stroke(im->cr);
+                cairo_restore(im->cr);
+            }
             break;
         default:
             break;