diff --git a/src/common/proto-irc.c b/src/common/proto-irc.c
index 7742c064..b19d9afa 100644
--- a/src/common/proto-irc.c
+++ b/src/common/proto-irc.c
@@ -1326,6 +1326,26 @@ process_named_servermsg (session *sess, char *buf, char *rawname, char *word_eol
 								  rawname, NULL, 0, tags_data->timestamp);
 }
 
+/* Returns the timezone offset. This should be the same as the variable
+ * "timezone" in time.h, but *BSD doesn't have it.
+ */
+static int
+get_timezone(void)
+{
+	struct tm tm_utc, tm_local;
+	time_t t, time_utc, time_local;
+
+	time (&t);
+
+	gmtime_r (&t, &tm_utc);
+	localtime_r (&t, &tm_local);
+
+	time_utc = mktime (&tm_utc);
+	time_local = mktime (&tm_local);
+
+	return time_utc - time_local;
+}
+
 /* Handle time-server tags.
  * 
  * Sets tags_data->timestamp to the correct time (in unix time). 
@@ -1370,7 +1390,7 @@ handle_message_tag_time (const char *time, message_tags_data *tags_data)
 		}
 
 		/* get rid of the local time (mktime() receives a local calendar time) */
-		tags_data->timestamp -= timezone;
+		tags_data->timestamp -= get_timezone();
 	}
 	else
 	{