diff --git a/lib/lib.error.c b/lib/lib.error.c
index 39897d270e..b364eda51b 100644
--- a/lib/lib.error.c
+++ b/lib/lib.error.c
@@ -119,7 +119,7 @@ void vlogmsg(int msglevel, const char *mesg, va_list ap)
 	for(str_tmp_pos=0; str_tmp_pos<strlen(progname_escaped); str_tmp_pos++) {
 		ctmp = progname_escaped[str_tmp_pos];
 		if ( ctmp!='%' ) {
-			progname_unformatted[esc_tmp_pos++] = ctmp;
+			progname_unformatted[esc_tmp_pos++] = 'c';
 		}
 	}
 	progname_unformatted[esc_tmp_pos] = 0;