diff --git a/wmsun/wmSun.c b/wmsun/wmSun.c
index 4e7094a..882bfca 100644
--- a/wmsun/wmSun.c
+++ b/wmsun/wmSun.c
@@ -147,7 +147,7 @@ int main(int argc, char *argv[]) {
    
 
    
-    openXwindow(argc, argv, wmSun_master, wmSun_mask_bits, wmSun_mask_width, wmSun_mask_height);
+    openXwindow(argc, argv, wmSun_master, (char *)wmSun_mask_bits, wmSun_mask_width, wmSun_mask_height);
 
 
 
diff --git a/wmsun/wmSun_mask.xbm b/wmsun/wmSun_mask.xbm
index f334241..0ebec55 100644
--- a/wmsun/wmSun_mask.xbm
+++ b/wmsun/wmSun_mask.xbm
@@ -1,6 +1,6 @@
 #define wmSun_mask_width 64
 #define wmSun_mask_height 64
-static char wmSun_mask_bits[] = {
+static unsigned char wmSun_mask_bits[] = {
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
  0x00,0x00,0xf0,0xff,0xff,0xff,0xff,0xff,0xff,0x07,0xf0,0xff,0xff,0xff,0xff,