Index: lib/libfetch/fetch.3
===================================================================
--- lib/libfetch/fetch.3	(revision 258921)
+++ lib/libfetch/fetch.3	(working copy)
@@ -627,6 +627,7 @@ the document URL will be used as referrer URL.
 Specifies the User-Agent string to use for HTTP requests.
 This can be useful when working with HTTP origin or proxy servers that
 differentiate between user agents.
+If used with an empty string no User-Agent is sent.
 .It Ev NETRC
 Specifies a file to use instead of
 .Pa ~/.netrc
Index: lib/libfetch/http.c
===================================================================
--- lib/libfetch/http.c	(revision 258921)
+++ lib/libfetch/http.c	(working copy)
@@ -1679,9 +1679,10 @@ http_request(struct url *URL, const char *op, stru
 			else
 				http_cmd(conn, "Referer: %s", p);
 		}
-		if ((p = getenv("HTTP_USER_AGENT")) != NULL && *p != '\0')
-			http_cmd(conn, "User-Agent: %s", p);
-		else
+		if ((p = getenv("HTTP_USER_AGENT")) != NULL) {
+			if  (*p != '\0')
+				http_cmd(conn, "User-Agent: %s", p);
+		} else
 			http_cmd(conn, "User-Agent: %s " _LIBFETCH_VER, getprogname());
 		if (url->offset > 0)
 			http_cmd(conn, "Range: bytes=%lld-", (long long)url->offset);