diff --git a/blaze822_priv.h b/blaze822_priv.h
index c871ca7..f1fe880 100644
--- a/blaze822_priv.h
+++ b/blaze822_priv.h
@@ -12,7 +12,8 @@ struct message {
 
 #define isfws(c)  (((unsigned char)(c) == ' ' || (unsigned char)(c) == '\t' || (unsigned char)(c) == '\n' || (unsigned char)(c) == '\r'))
 
-// ASCII lowercase without alpha check (wrong for "@[\]^_")
+// ASCII lowercase/uppercase without alpha check (wrong for "@[\]^_")
 #define lc(c) ((c) | 0x20)
+#define uc(c) ((c) & 0xdf)
 
 void *mymemmem(const void *h0, size_t k, const void *n0, size_t l);
diff --git a/mflag.c b/mflag.c
index a5a6005..7708946 100644
--- a/mflag.c
+++ b/mflag.c
@@ -12,8 +12,7 @@
 #include <unistd.h>
 
 #include "blaze822.h"
-
-#define uc(c) ((c) & 0xdf)
+#include "blaze822_priv.h"
 
 static int8_t flags[255];
 static int vflag = 0;
diff --git a/mlist.c b/mlist.c
index 9d0800f..6fcfb66 100644
--- a/mlist.c
+++ b/mlist.c
@@ -12,9 +12,7 @@
 #include <unistd.h>
 
 #include "blaze822.h"
-
-#define lc(c) ((c) | 0x20)
-#define uc(c) ((c) & 0xdf)
+#include "blaze822_priv.h"
 
 /*