diff -uN netpbm-10.31/converter/other/pnmtopng.c.ORG netpbm-10.31/converter/other/pnmtopng.c
--- netpbm-10.31/converter/other/pnmtopng.c.ORG	Mon Oct 17 04:36:43 2005
+++ netpbm-10.31/converter/other/pnmtopng.c	Fri Feb 17 10:44:02 2006
@@ -296,7 +296,7 @@
     OPTENT3(0, "ztxt",             OPT_STRING,    &cmdlineP->ztxt,
             &ztxtSpec,             0);
     OPTENT3(0, "modtime",          OPT_STRING,    &modtime,
-            &modtimeSpec,          0);
+            &cmdlineP->modtimeSpec,          0);
     OPTENT3(0, "palette",          OPT_STRING,    &cmdlineP->palette,
             &paletteSpec,          0);
     OPTENT3(0, "compression",      OPT_UINT,