diff --git a/source/cl_main.c b/source/cl_main.c
index 92b9dbd..956dc23 100644
--- a/source/cl_main.c
+++ b/source/cl_main.c
@@ -864,9 +864,9 @@ void CL_ConnectionlessPacket (void)
 
 		s = MSG_ReadString ();
 
-		while (*s && isspace(*s))
+		while (*s && isspace((int)*s))
 			s++;
-		while (*s && isspace(s[strlen(s) - 1]))
+		while (*s && isspace((int)(s[strlen(s) - 1])))
 			s[strlen(s) - 1] = 0;
 
 		if (!allowremotecmd && (!*localid.string || strcmp(localid.string, s))) {
diff --git a/source/sv_user.c b/source/sv_user.c
index 0f2adee..5cc127b 100644
--- a/source/sv_user.c
+++ b/source/sv_user.c
@@ -693,7 +693,7 @@ void SV_BeginDownload_f(void)
 		char *p;
 
 		for (p = name; *p; p++)
-			*p = (char)tolower(*p);
+			*p = tolower((int)*p);
 	}