diff -urN pnm2ppa-1.12/calibrate_ppa.c pnm2ppa-1.12.new/calibrate_ppa.c
--- pnm2ppa-1.12/calibrate_ppa.c	Mon Jun 10 01:46:19 2002
+++ pnm2ppa-1.12.new/calibrate_ppa.c	Mon Sep 15 07:57:28 2003
@@ -78,7 +78,7 @@
   FILE *outFile = NULL ;
   int testPattern = 0;
   char *out_filepath = NULL;
-  char c;
+  int c;
   static struct option long_opts[] = {
     {"gamma",0,0,'g'},
     {"align",0,0,0},
diff -urN pnm2ppa-1.12/pnm2ppa.c pnm2ppa-1.12.new/pnm2ppa.c
--- pnm2ppa-1.12/pnm2ppa.c	Sat Nov  9 15:47:47 2002
+++ pnm2ppa-1.12.new/pnm2ppa.c	Mon Sep 15 07:57:03 2003
@@ -626,7 +626,7 @@
   int i, opt_index;
   FILE *in = NULL, *out = NULL, *gf = NULL;
   struct stat tmpstat;
-  char c;
+  int c;
   BOOLEAN get_Gamma = true;
 
   char gammaFile[MAXPATHLEN];