diff --git a/include/asterisk/channel.h b/include/asterisk/channel.h
index c5268a657f4f0598bdf2fa99f360d50e66f13a05..b12121947e97d1e644fffcd2c04025694f74a9c6 100755
--- a/include/asterisk/channel.h
+++ b/include/asterisk/channel.h
@@ -100,7 +100,7 @@ struct ast_channel {
 	/*! Lock, can be used to lock a channel for some operations */
 	ast_mutex_t lock;			
 	/*! Procedure causing blocking */
-	char *blockproc;			
+	const char *blockproc;			
 
 	/*! Current application */
 	char *appl;