diff --git a/frox/save_acl.cgi b/frox/save_acl.cgi
index 23be58bb5..d6207c9f2 100755
--- a/frox/save_acl.cgi
+++ b/frox/save_acl.cgi
@@ -69,14 +69,14 @@ return $_[0] =~ /^\d+$/ ? undef : $text{'acl_erate'};
 
 sub check_ntp
 {
-return $_[0] =~ /^(\S+):(\d+)$/ && gethostbyname($1) ? undef
+return $_[0] =~ /^(\S+):(\d+)$/ && &to_ipaddress("$1") ? undef
 						     : $text{'acl_entp'};
 }
 
 
 sub valid_srcdest
 {
-return gethostbyname($_[0]) ||
+return &to_ipaddress($_[0]) ||
 	   ($_[0] =~ /^([0-9\.]+)\/(\d+)$/ &&
 	    &check_ipaddress($1) && $2 > 0 && $2 <= 32) ||
 	   ($_[0] =~ /^([0-9\.]+)\/([0-9\.]+)$/ &&
diff --git a/frox/save_cache.cgi b/frox/save_cache.cgi
index e106f6822..de869d69c 100755
--- a/frox/save_cache.cgi
+++ b/frox/save_cache.cgi
@@ -40,7 +40,7 @@ return $_[0] =~ /^\d+$/ ? undef : $text{'cache_esize'};
 
 sub check_proxy
 {
-return $_[0] =~ /^(\S+):(\d+)$/ && gethostbyname($1) ?
+return $_[0] =~ /^(\S+):(\d+)$/ && &to_ipaddress($1) ?
 	undef : $text{'cache_eproxy'};
 }
 
diff --git a/frox/save_iptables.cgi b/frox/save_iptables.cgi
index 8f18e7ddd..f0af837ae 100755
--- a/frox/save_iptables.cgi
+++ b/frox/save_iptables.cgi
@@ -10,7 +10,7 @@ $port = &find_value("Port", $conf);
 
 # Validate inputs
 if ($in{'enabled'} == 1) {
-	gethostbyname($in{'net'}) ||
+	&to_ipaddress($in{'net'}) ||
 	    ($in{'net'} =~ /^([0-9\.]+)\/(\d+)$/ &&
 	     &check_ipaddress($1) && $2 > 0 && $2 <= 32) ||
 		&error($text{'iptables_enet'});
diff --git a/frox/save_net.cgi b/frox/save_net.cgi
index a34226056..13f30ea42 100755
--- a/frox/save_net.cgi
+++ b/frox/save_net.cgi
@@ -24,7 +24,7 @@ $conf = &get_config();
 
 sub check_listen
 {
-return gethostbyname($_[0]) ? undef : $text{'net_ehost'};
+return &to_ipaddress($_[0]) ? undef : $text{'net_ehost'};
 }
 
 sub check_port
@@ -39,7 +39,8 @@ return $_[0] =~ /^[a-z]+(\d*)(:\d+)?$/ ? undef : $text{'net_eiface'};
 
 sub check_proxy
 {
-return $_[0] =~ /^(\S+):(\d+)$/ && gethostbyname($1) ? undef : $text{'net_eproxy'};
+return $_[0] =~ /^(\S+):(\d+)$/ && &to_ipaddress($1) ?
+	undef : $text{'net_eproxy'};
 }
 
 sub check_ip