diff --git a/contrib/ipfilter/lib/ipf_perror.c b/contrib/ipfilter/lib/ipf_perror.c
index 85a1b1d66e2..08e31648b05 100644
--- a/contrib/ipfilter/lib/ipf_perror.c
+++ b/contrib/ipfilter/lib/ipf_perror.c
@@ -10,7 +10,7 @@ ipf_perror(err, string)
 	if (err == 0)
 		fprintf(stderr, "%s\n", string);
 	else
-		fprintf(stderr, "%s %s\n", string, ipf_strerror(err));
+		fprintf(stderr, "%s: %s\n", string, ipf_strerror(err));
 }
 
 int