diff -Naur netpbm-orig/converter/other/pnmtopng.c netpbm/converter/other/pnmtopng.c
--- netpbm-orig/converter/other/pnmtopng.c	2010-01-22 00:13:48.000000000 -0500
+++ netpbm/converter/other/pnmtopng.c	2010-01-22 00:21:33.000000000 -0500
@@ -2641,7 +2641,7 @@
         info_ptr->color_type == PNG_COLOR_TYPE_RGB) {
         if (transparent > 0) {
             info_ptr->valid |= PNG_INFO_tRNS;
-            info_ptr->trans_values = 
+            info_ptr->trans_color = 
                 xelToPngColor_16(transcolor, maxval, png_maxval);
         }
     } else {
@@ -2653,10 +2653,10 @@
         if (info_ptr->valid && PNG_INFO_tRNS) 
             pm_message("Transparent color {gray, red, green, blue} = "
                        "{%d, %d, %d, %d}",
-                       info_ptr->trans_values.gray,
-                       info_ptr->trans_values.red,
-                       info_ptr->trans_values.green,
-                       info_ptr->trans_values.blue);
+                       info_ptr->trans_color.gray,
+                       info_ptr->trans_color.red,
+                       info_ptr->trans_color.green,
+                       info_ptr->trans_color.blue);
         else
             pm_message("No transparent color");
     }
diff -Naur netpbm-orig/converter/other/pngtopnm.c netpbm/converter/other/pngtopnm.c
--- netpbm-orig/converter/other/pngtopnm.c	2010-01-22 00:33:25.000000000 -0500
+++ netpbm/converter/other/pngtopnm.c	2010-01-22 00:39:21.000000000 -0500
@@ -569,8 +569,8 @@
             for (i = 0, foundGray = FALSE;
                  i < info_ptr->num_trans && !foundGray;
                  ++i) {
-                if (info_ptr->trans[i] != 0 &&
-                    info_ptr->trans[i] != maxval) {
+                if (info_ptr->trans_alpha[i] != 0 &&
+                    info_ptr->trans_alpha[i] != maxval) {
                     foundGray = TRUE;
                 }
             }
@@ -641,7 +641,7 @@
                 unsigned int i;
                 trans_mix = TRUE;
                 for (i = 0; i < info_ptr->num_trans; ++i)
-                    if (info_ptr->trans[i] != 0 && info_ptr->trans[i] != 255) {
+                    if (info_ptr->trans_alpha[i] != 0 && info_ptr->trans_alpha[i] != 255) {
                         trans_mix = FALSE;
                         break;
                     }
@@ -1061,7 +1061,7 @@
             setXel(&xelrow[col], fgColor, bgColor, alphaHandling,
                    (pngxP->info_ptr->valid & PNG_INFO_tRNS) &&
                    index < pngxP->info_ptr->num_trans ?
-                   pngxP->info_ptr->trans[index] : maxval);
+                   pngxP->info_ptr->trans_alpha[index] : maxval);
         }
         break;