--- chan_sip.c-old	2004-05-08 11:50:49.000000000 -0400
+++ chan_sip.c	2004-05-08 12:29:30.000000000 -0400
@@ -1976,7 +1976,7 @@
 		*hostname = '\0';
 		hostname++;
 	}
-	if (!username || ast_strlen_zero(username) || !hostname || !strlen(hostname)) {
+	if (!username || ast_strlen_zero(username) || !hostname || ast_strlen_zero(hostname)) {
 		ast_log(LOG_WARNING, "Format for registration is user[:secret[:authuser]]@host[:port][/contact] at line %d", lineno);
 		return -1;
 	}
@@ -3122,9 +3122,9 @@
 		l = p->fromuser;
 
 	if ((ourport != 5060) && ast_strlen_zero(p->fromdomain))
-		snprintf(from, sizeof(from), "\"%s\" <sip:%s@%s:%d>;tag=as%08x", n, l, strlen(p->fromdomain) ? p->fromdomain : inet_ntoa(p->ourip), ourport, p->tag);
+		snprintf(from, sizeof(from), "\"%s\" <sip:%s@%s:%d>;tag=as%08x", n, l, ast_strlen_zero(p->fromdomain) ? inet_ntoa(p->ourip) : p->fromdomain, ourport, p->tag);
 	else
-		snprintf(from, sizeof(from), "\"%s\" <sip:%s@%s>;tag=as%08x", n, l, strlen(p->fromdomain) ? p->fromdomain : inet_ntoa(p->ourip), p->tag);
+		snprintf(from, sizeof(from), "\"%s\" <sip:%s@%s>;tag=as%08x", n, l, ast_strlen_zero(p->fromdomain) ? inet_ntoa(p->ourip) : p->fromdomain, p->tag);
 
 	if (!ast_strlen_zero(p->username)) {
 		if (ntohs(p->sa.sin_port) != DEFAULT_SIP_PORT) {
@@ -4754,8 +4754,8 @@
 	if (peer) {
 		ast_cli(fd,"\n\n");
 		ast_cli(fd, "  * Name       : %s\n", peer->name);
-		ast_cli(fd, "  Secret       : %s\n", strlen(peer->secret)?"<Set>":"<Not set>");
-		ast_cli(fd, "  MD5Secret    : %s\n", strlen(peer->md5secret)?"<Set>":"<Not set>");
+		ast_cli(fd, "  Secret       : %s\n", ast_strlen_zero(peer->secret)?"<Not set>":"<Set>");
+		ast_cli(fd, "  MD5Secret    : %s\n", ast_strlen_zero(peer->md5secret)?"<Not set>":"<Set>");
 		ast_cli(fd, "  Context      : %s\n", peer->context);
 		ast_cli(fd, "  Methods      : %s\n", peer->methods);
 		ast_cli(fd, "  Language     : %s\n", peer->language);
@@ -4994,7 +4994,7 @@
 	if (!strcasecmp(get_header(req, "Content-Type"), "application/dtmf-relay")) {
 
 		/* Try getting the "signal=" part */
-		if (strlen(c = get_sdp(req, "Signal")) || strlen(c = get_sdp(req, "d"))) {
+		if (ast_strlen_zero(c = get_sdp(req, "Signal")) && ast_strlen_zero(c = get_sdp(req, "d"))) {
 		   strncpy(buf, c, sizeof(buf) - 1);
 		} else {
 		   ast_log(LOG_WARNING, "Unable to retrieve DTMF signal from INFO message from %s\n", p->callid);