diff --git a/src/common/url.c b/src/common/url.c
index 808a73de..a3922345 100644
--- a/src/common/url.c
+++ b/src/common/url.c
@@ -415,7 +415,7 @@ regex_match (const GRegex *re, const char *word, int *start, int *end)
 }
 
 /*	Miscellaneous description --- */
-#define DOMAIN "[a-z0-9][-a-z0-9]*(\\.[-a-z0-9]+)*"
+#define DOMAIN "[_a-z0-9][-_a-z0-9]*(\\.[-_a-z0-9]+)*"
 #define TLD "\\.[a-z][-a-z0-9]*[a-z]"
 #define IPADDR "[0-9]{1,3}(\\.[0-9]{1,3}){3}"
 #define IPV6GROUP "([0-9a-f]{0,4})"
@@ -610,7 +610,7 @@ re_url (void)
 }
 
 /*	EMAIL description --- */
-#define EMAIL "[a-z][-_a-z0-9]+@" "(" HOST_URL ")"
+#define EMAIL "[a-z][._%+-a-z0-9]+@" "(" HOST_URL ")"
 
 static const GRegex *
 re_email (void)