diff --git a/src/netif/ppp/auth.c b/src/netif/ppp/auth.c
index 72b40561..614549d0 100644
--- a/src/netif/ppp/auth.c
+++ b/src/netif/ppp/auth.c
@@ -223,15 +223,15 @@ struct notifier *link_down_notifier = NULL;
 bool uselogin = 0;		/* Use /etc/passwd for checking PAP */
 bool session_mgmt = 0;		/* Do session management (login records) */
 bool cryptpap = 0;		/* Passwords in pap-secrets are encrypted */
-//bool refuse_pap = 0;		/* Don't wanna auth. ourselves with PAP */
-//bool refuse_chap = 0;		/* Don't wanna auth. ourselves with CHAP */
-//bool refuse_eap = 0;		/* Don't wanna auth. ourselves with EAP */
+bool refuse_pap = 0;		/* Don't wanna auth. ourselves with PAP */
+bool refuse_chap = 0;		/* Don't wanna auth. ourselves with CHAP */
+bool refuse_eap = 0;		/* Don't wanna auth. ourselves with EAP */
 #if MSCHAP_SUPPORT
-//bool refuse_mschap = 0;		/* Don't wanna auth. ourselves with MS-CHAP */
-//bool refuse_mschap_v2 = 0;	/* Don't wanna auth. oif 0 /* UNUSED */urselves with MS-CHAPv2 */
+bool refuse_mschap = 0;		/* Don't wanna auth. ourselves with MS-CHAP */
+bool refuse_mschap_v2 = 0;	/* Don't wanna auth. ourselves with MS-CHAPv2 */
 #else /* MSCHAP_SUPPORT */
-//bool refuse_mschap = 1;		/* Don't wanna auth. ourselves with MS-CHAP */
-//bool refuse_mschap_v2 = 1;	/* Don't wanna auth. ourselves with MS-CHAPv2 */
+bool refuse_mschap = 1;		/* Don't wanna auth. ourselves with MS-CHAP */
+bool refuse_mschap_v2 = 1;	/* Don't wanna auth. ourselves with MS-CHAPv2 */
 #endif /* MSCHAP_SUPPORT */
 #endif /* MOVED TO ppp_settings */
 #if 0 /* UNUSED */
@@ -1079,7 +1079,9 @@ auth_peer_success(unit, protocol, prot_flavor, name, namelen)
 	namelen = sizeof(peer_authname) - 1;
     MEMCPY(peer_authname, name, namelen);
     peer_authname[namelen] = 0;
-    //script_setenv("PEERNAME", peer_authname, 0);
+#if 0 /* UNUSED */
+    script_setenv("PEERNAME", peer_authname, 0);
+#endif /* UNUSED */
 
     /* Save the authentication method for later. */
     auth_done[unit] |= bit;
@@ -1538,7 +1540,7 @@ auth_reset(unit)
 #endif /* EAP_SUPPORT */
 
 #if 0 /* OLD CODE */
-    //ao->neg_upap = !ppp_settings.refuse_pap && (ppp_settings.passwd[0] != 0 || get_pap_passwd(NULL));
+    ao->neg_upap = !ppp_settings.refuse_pap && (ppp_settings.passwd[0] != 0 || get_pap_passwd(NULL));
 
     /*
     ao->neg_chap = (!ppp_settings.refuse_chap || !refuse_mschap || !refuse_mschap_v2)
@@ -1978,7 +1980,7 @@ get_secret(unit, client, server, secret, secret_len, am_server)
 
 /* FIXME: clean that */
 #if 0
-	    //	strlcpy(rname, ppp_settings.user, sizeof(rname));
+	    	strlcpy(rname, ppp_settings.user, sizeof(rname));
 
 
 /*
diff --git a/src/netif/ppp/ipcp.c b/src/netif/ppp/ipcp.c
index 992db3cd..6d94ec30 100644
--- a/src/netif/ppp/ipcp.c
+++ b/src/netif/ppp/ipcp.c
@@ -304,7 +304,7 @@ struct protent ipcp_protent = {
 #endif /* DEMAND_SUPPORT */
 };
 
-static void ipcp_clear_addrs __P((int, u_int32_t, u_int32_t, bool));
+static void ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, bool replacedefaultroute);
 
 /*
  * Lengths of configuration options.
@@ -2038,13 +2038,8 @@ ipcp_down(f)
  * ipcp_clear_addrs() - clear the interface addresses, routes,
  * proxy arp entries, etc.
  */
-static void
-ipcp_clear_addrs(unit, ouraddr, hisaddr, replacedefaultroute)
-    int unit;
-    u_int32_t ouraddr;  /* local address */
-    u_int32_t hisaddr;  /* remote address */
-    bool replacedefaultroute;
-{
+static void ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, bool replacedefaultroute) {
+
     if (proxy_arp_set[unit]) {
 	cifproxyarp(unit, hisaddr);
 	proxy_arp_set[unit] = 0;
diff --git a/src/netif/ppp/lcp.c b/src/netif/ppp/lcp.c
index 52ca0fee..645da392 100644
--- a/src/netif/ppp/lcp.c
+++ b/src/netif/ppp/lcp.c
@@ -731,22 +731,27 @@ lcp_cilen(f)
 #if EAP_SUPPORT
 	    LENCISHORT(go->neg_eap) +
 #endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-	    LENCICHAP(
+#if CHAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
 #if EAP_SUPPORT
-	        !go->neg_eap &&
+	    LENCICHAP(!go->neg_eap && go->neg_chap) +
 #endif /* EAP_SUPPORT */
-	        go->neg_chap) +
+#if !EAP_SUPPORT
+	    LENCICHAP(go->neg_chap) +
+#endif /* !EAP_SUPPORT */
 #endif /* CHAP_SUPPORT */
-#if PAP_SUPPORT
-	    LENCISHORT(
-#if EAP_SUPPORT
-	        !go->neg_eap &&
-#endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-	        !go->neg_chap &&
-#endif /* CHAP_SUPPORT */
-	        go->neg_upap) +
+#if PAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
+#if EAP_SUPPORT && CHAP_SUPPORT
+	    LENCISHORT(!go->neg_eap && !go->neg_chap && go->neg_upap) +
+#endif /* EAP_SUPPORT && CHAP_SUPPORT */
+#if EAP_SUPPORT && !CHAP_SUPPORT
+	    LENCISHORT(!go->neg_eap && go->neg_upap) +
+#endif /* EAP_SUPPORT && !CHAP_SUPPORT */
+#if !EAP_SUPPORT && CHAP_SUPPORT
+	    LENCISHORT(!go->neg_chap && go->neg_upap) +
+#endif /* !EAP_SUPPORT && CHAP_SUPPORT */
+#if !EAP_SUPPORT && !CHAP_SUPPORT
+	    LENCISHORT(go->neg_upap) +
+#endif /* !EAP_SUPPORT && !CHAP_SUPPORT */
 #endif /* PAP_SUPPORT */
 	    LENCILQR(go->neg_lqr) +
 	    LENCICBCP(go->neg_cbcp) +
@@ -826,22 +831,27 @@ lcp_addci(f, ucp, lenp)
 #if EAP_SUPPORT
     ADDCISHORT(CI_AUTHTYPE, go->neg_eap, PPP_EAP);
 #endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-    ADDCICHAP(CI_AUTHTYPE,
+#if CHAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
 #if EAP_SUPPORT
-        !go->neg_eap &&
+    ADDCICHAP(CI_AUTHTYPE, !go->neg_eap && go->neg_chap, go->chap_mdtype);
 #endif /* EAP_SUPPORT */
-        go->neg_chap, go->chap_mdtype);
+#if !EAP_SUPPORT
+    ADDCICHAP(CI_AUTHTYPE, go->neg_chap, go->chap_mdtype);
+#endif /* !EAP_SUPPORT */
 #endif /* CHAP_SUPPORT */
-#if PAP_SUPPORT
-    ADDCISHORT(CI_AUTHTYPE,
-#if EAP_SUPPORT
-        !go->neg_eap &&
-#endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-        !go->neg_chap &&
-#endif /* CHAP_SUPPORT */
-        go->neg_upap, PPP_PAP);
+#if PAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
+#if EAP_SUPPORT && CHAP_SUPPORT
+    ADDCISHORT(CI_AUTHTYPE, !go->neg_eap && !go->neg_chap && go->neg_upap, PPP_PAP);
+#endif /* EAP_SUPPORT && CHAP_SUPPORT */
+#if EAP_SUPPORT && !CHAP_SUPPORT
+    ADDCISHORT(CI_AUTHTYPE, !go->neg_eap && go->neg_upap, PPP_PAP);
+#endif /* EAP_SUPPORT && !CHAP_SUPPORT */
+#if !EAP_SUPPORT && CHAP_SUPPORT
+    ADDCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
+#endif /* !EAP_SUPPORT && CHAP_SUPPORT */
+#if !EAP_SUPPORT && !CHAP_SUPPORT
+    ADDCISHORT(CI_AUTHTYPE, go->neg_upap, PPP_PAP);
+#endif /* !EAP_SUPPORT && !CHAP_SUPPORT */
 #endif /* PAP_SUPPORT */
     ADDCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
     ADDCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
@@ -993,22 +1003,27 @@ lcp_ackci(f, p, len)
 #if EAP_SUPPORT
     ACKCISHORT(CI_AUTHTYPE, go->neg_eap, PPP_EAP);
 #endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-    ACKCICHAP(CI_AUTHTYPE,
+#if CHAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
 #if EAP_SUPPORT
-        !go->neg_eap &&
+    ACKCICHAP(CI_AUTHTYPE, !go->neg_eap && go->neg_chap, go->chap_mdtype);
 #endif /* EAP_SUPPORT */
-        go->neg_chap, go->chap_mdtype);
+#if !EAP_SUPPORT
+    ACKCICHAP(CI_AUTHTYPE, go->neg_chap, go->chap_mdtype);
+#endif /* !EAP_SUPPORT */
 #endif /* CHAP_SUPPORT */
-#if PAP_SUPPORT
-    ACKCISHORT(CI_AUTHTYPE,
-#if EAP_SUPPORT
-        !go->neg_eap &&
-#endif /* EAP_SUPPORT */
-#if CHAP_SUPPORT
-        !go->neg_chap &&
-#endif /* CHAP_SUPPORT */
-        go->neg_upap, PPP_PAP);
+#if PAP_SUPPORT /* cannot be improved, embedding a directive within macro arguments is not portable */
+#if EAP_SUPPORT && CHAP_SUPPORT
+    ACKCISHORT(CI_AUTHTYPE, !go->neg_eap && !go->neg_chap && go->neg_upap, PPP_PAP);
+#endif /* EAP_SUPPORT && CHAP_SUPPORT */
+#if EAP_SUPPORT && !CHAP_SUPPORT
+    ACKCISHORT(CI_AUTHTYPE, !go->neg_eap && go->neg_upap, PPP_PAP);
+#endif /* EAP_SUPPORT && !CHAP_SUPPORT */
+#if !EAP_SUPPORT && CHAP_SUPPORT
+    ACKCISHORT(CI_AUTHTYPE, !go->neg_chap && go->neg_upap, PPP_PAP);
+#endif /* !EAP_SUPPORT && CHAP_SUPPORT */
+#if !EAP_SUPPORT && !CHAP_SUPPORT
+    ACKCISHORT(CI_AUTHTYPE, go->neg_upap, PPP_PAP);
+#endif /* !EAP_SUPPORT && !CHAP_SUPPORT */
 #endif /* PAP_SUPPORT */
     ACKCILQR(CI_QUALITY, go->neg_lqr, go->lqr_period);
     ACKCICHAR(CI_CALLBACK, go->neg_cbcp, CBCP_OPT);
diff --git a/src/netif/ppp/options.c b/src/netif/ppp/options.c
index 620a2e6d..fbe3404a 100644
--- a/src/netif/ppp/options.c
+++ b/src/netif/ppp/options.c
@@ -50,7 +50,9 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <stdlib.h>
-//#include <syslog.h>
+#if 0
+#include <syslog.h>
+#endif
 #include <string.h>
 #include <pwd.h>
 #ifdef PLUGIN
@@ -94,12 +96,16 @@ struct option_value {
 int	debug = 0;		/* Debug flag */
 int	kdebugflag = 0;		/* Tell kernel to print debug messages */
 int	default_device = 1;	/* Using /dev/tty or equivalent */
-//char	devnam[MAXPATHLEN];	/* Device name */
+#if 0
+char	devnam[MAXPATHLEN];	/* Device name */
+#endif
 bool	nodetach = 0;		/* Don't detach from controlling tty */
 bool	updetach = 0;		/* Detach once link is up */
 int	maxconnect = 0;		/* Maximum connect time */
-//char	user[MAXNAMELEN];	/* Username for PAP */
-//char	passwd[MAXSECRETLEN];	/* Password for PAP */
+#if 0
+char	user[MAXNAMELEN];	/* Username for PAP */
+char	passwd[MAXSECRETLEN];	/* Password for PAP */
+#endif
 bool	persist = 0;		/* Reopen link after it goes down */
 char	our_name[MAXNAMELEN];	/* Our name for authentication purposes */
 #if DEMAND_SUPPORT
@@ -114,14 +120,18 @@ int	log_to_fd = 1;		/* send log messages to this fd too */
 #endif
 bool	log_default = 1;	/* log_to_fd is default (stdout) */
 int	maxfail = 10;		/* max # of unsuccessful connection attempts */
-//char	linkname[MAXPATHLEN];	/* logical name for link */
+#if 0
+char	linkname[MAXPATHLEN];	/* logical name for link */
+#endif
 bool	tune_kernel;		/* may alter kernel settings */
 int	connect_delay = 1000;	/* wait this many ms after connect script */
 int	req_unit = -1;		/* requested interface unit */
 bool	multilink = 0;		/* Enable multilink operation */
 char	*bundle_name = NULL;	/* bundle name for multilink */
 bool	dump_options;		/* print out option values */
-//bool	dryrun;			/* print out option values and exit */
+#if 0
+bool	dryrun;			/* print out option values and exit */
+#endif
 char	*domain;		/* domain name set by domain option */
 int	child_wait = 5;		/* # seconds to wait for children at exit */
 
diff --git a/src/netif/ppp/ppp.c b/src/netif/ppp/ppp.c
index 79fc54db..49476b24 100644
--- a/src/netif/ppp/ppp.c
+++ b/src/netif/ppp/ppp.c
@@ -736,7 +736,7 @@ void pppInProcOverEthernet(int pd, struct pbuf *pb) {
 
 drop:
   LINK_STATS_INC(link.drop);
-//  snmp_inc_ifindiscards(&pppControl[pd].netif);
+  snmp_inc_ifindiscards(&pppControl[pd].netif);
   pbuf_free(pb);
   return;
 }
@@ -744,8 +744,10 @@ drop:
 void pppOverEthernetInitFailed(int pd) {
   PPPControl* pc;
 
-  //pppHup(pd);
-  //pppStop(pd);
+  /* FIXME: re-enable that
+   * pppHup(pd);
+   * pppStop(pd);
+   */
 
   pc = &pppControl[pd];
   pppoe_destroy(&pc->netif);
@@ -827,7 +829,7 @@ static err_t pppifOutput(struct netif *netif, struct pbuf *pb, ip_addr_t *ipaddr
    * and the peer will just drop it if it's not accepting it. */
   if (pd < 0 || pd >= NUM_PPP || !pc->openFlag || !pb) {
     PPPDEBUG(LOG_WARNING, ("pppifOutput[%d]: bad parms prot=%d pb=%p\n",
-              pd, PPP_IP, pb));
+              pd, PPP_IP, (void*)pb));
     LINK_STATS_INC(link.opterr);
     LINK_STATS_INC(link.drop);
     snmp_inc_ifoutdiscards(netif);
@@ -1168,8 +1170,10 @@ int sifaddr (int unit, u_int32_t our_adr, u_int32_t his_adr,
     SMEMCPY(&pc->addrs.our_ipaddr, &our_adr, sizeof(our_adr));
     SMEMCPY(&pc->addrs.his_ipaddr, &his_adr, sizeof(his_adr));
     SMEMCPY(&pc->addrs.netmask, &net_mask, sizeof(net_mask));
-//    SMEMCPY(&pc->addrs.dns1, &ns1, sizeof(ns1));
-//    SMEMCPY(&pc->addrs.dns2, &ns2, sizeof(ns2));
+/* FIXME: re-enable DNS
+ *    SMEMCPY(&pc->addrs.dns1, &ns1, sizeof(ns1));
+ *    SMEMCPY(&pc->addrs.dns2, &ns2, sizeof(ns2));
+ */
   }
   return st;
 }
diff --git a/src/netif/ppp/ppp.h b/src/netif/ppp/ppp.h
index 502b539d..d5123724 100644
--- a/src/netif/ppp/ppp.h
+++ b/src/netif/ppp/ppp.h
@@ -281,8 +281,8 @@ struct ppp_settings {
   char user       [MAXNAMELEN   + 1]; /* Username for PAP */
   char passwd     [MAXSECRETLEN + 1]; /* Password for PAP, secret for CHAP */
   char our_name   [MAXNAMELEN   + 1]; /* Our name for authentication purposes */
-  // FIXME: re-enable that
-  //  char remote_name[MAXNAMELEN   + 1]; /* Peer's name for authentication */
+  /* FIXME: re-enable that */
+  /*  char remote_name[MAXNAMELEN   + 1]; */ /* Peer's name for authentication */
 };
 
 struct ppp_settings ppp_settings;
@@ -315,12 +315,12 @@ int ppp_init(void);
  *
  */
 enum pppAuthType {
-    PPPAUTHTYPE_NONE,
-    PPPAUTHTYPE_ANY,
-    PPPAUTHTYPE_PAP,
 #if CHAP_SUPPORT
     PPPAUTHTYPE_CHAP,
 #endif /* CHAP_SUPPORT */
+    PPPAUTHTYPE_PAP,
+    PPPAUTHTYPE_ANY,
+    PPPAUTHTYPE_NONE
 };
 
 int ppp_init(void);
@@ -511,7 +511,7 @@ int  get_secret __P((int, char *, char *, char *, int *, int));
 				/* get "secret" for chap */
 
 /* Procedures exported from ipcp.c */
-//int parse_dotted_ip __P((char *, u_int32_t *));
+/* int parse_dotted_ip __P((char *, u_int32_t *)); */
 
 /* Procedures exported from demand.c */
 #if DEMAND_SUPPORT
diff --git a/src/netif/ppp/tty.c b/src/netif/ppp/tty.c
index 1476c1d1..53941c6e 100644
--- a/src/netif/ppp/tty.c
+++ b/src/netif/ppp/tty.c
@@ -950,7 +950,7 @@ start_charshunt(ifd, ofd)
 {
     int cpid;
 
-    cpid = -1; // safe_fork(ifd, ofd, (log_to_fd >= 0? log_to_fd: 2));
+    cpid = -1; /* safe_fork(ifd, ofd, (log_to_fd >= 0? log_to_fd: 2)); */
     if (cpid == -1) {
 	error("Can't fork process for character shunt: %m");
 	return 0;
diff --git a/src/netif/ppp/utils.c b/src/netif/ppp/utils.c
index 03b9c373..4dc4080e 100644
--- a/src/netif/ppp/utils.c
+++ b/src/netif/ppp/utils.c
@@ -40,7 +40,9 @@
 #include <signal.h>
 #include <errno.h>
 #include <fcntl.h>
-//#include <syslog.h>
+#if 0
+#include <syslog.h>
+#endif
 #include <netdb.h>
 #include <time.h>
 #include <utmp.h>
@@ -678,7 +680,7 @@ log_write(level, buf)
     char *buf;
 {
 /* FIXME: replace this with a log callback */
-    // if(level >= min_log_level) /* FIXME: add a minimum log level */
+    /* if(level >= min_log_level) */ /* FIXME: add a minimum log level */
     printf("LOG: %s\n", buf);
 #if 0
     if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) {