diff -urN ./plugins/check_snmp.c ../plugins/plugins/check_snmp.c
--- ./plugins/check_snmp.c	2005-01-24 08:29:54.000000000 +0100
+++ ../plugins/plugins/check_snmp.c	2005-02-17 16:53:58.000000000 +0100
@@ -36,6 +36,7 @@
 #define DEFAULT_AUTH_PROTOCOL "MD5"
 #define DEFAULT_DELIMITER "="
 #define DEFAULT_OUTPUT_DELIMITER " "
+#define DEFAULT_SEC_LEVEL "noAuthNoPriv"
 
 #define mark(a) ((a)!=0?"*":"")
 
@@ -88,12 +89,12 @@
 #endif
 
 char *server_address = NULL;
-char *community = NULL;
+char *community = DEFAULT_COMMUNITY;
 char *authpriv = NULL;
-char *proto = NULL;
-char *seclevel = NULL;
+char *proto = DEFAULT_PROTOCOL;
+char *seclevel = DEFAULT_SEC_LEVEL;
 char *secname = NULL;
-char *authproto = NULL;
+char *authproto = DEFAULT_AUTH_PROTOCOL;
 char *authpasswd = NULL;
 char *privpasswd = NULL;
 char *oid;
@@ -147,15 +148,15 @@
 		eval_method[i] = CHECK_UNDEF;
 	i = 0;
 
-	oid = strdup ("");
-	label = strdup ("SNMP");
-	units = strdup ("");
-	port = strdup (DEFAULT_PORT);
-	outbuff = strdup ("");
-	output = strdup ("");
-	delimiter = strdup (DEFAULT_DELIMITER);
-	output_delim = strdup (DEFAULT_OUTPUT_DELIMITER);
-	miblist = strdup (DEFAULT_MIBLIST);
+	oid = "";
+	label = "SNMP";
+	units = "";
+	port = DEFAULT_PORT;
+	outbuff = "";
+	output = "";
+	delimiter = DEFAULT_DELIMITER;
+	output_delim = DEFAULT_OUTPUT_DELIMITER;
+	miblist = DEFAULT_MIBLIST;
 	timeout_interval = DEFAULT_TIMEOUT;
 	retries = DEFAULT_RETRIES;
 
@@ -598,9 +599,6 @@
 	if (server_address == NULL)
 		server_address = argv[optind];
 
-	if (community == NULL)
-		community = strdup (DEFAULT_COMMUNITY);
-
 	return validate_arguments ();
 }
 
@@ -631,30 +629,28 @@
 validate_arguments ()
 {
 
-	/* Need better checks to verify seclevel and authproto choices */
-	
-	if (seclevel == NULL) 
-		asprintf (&seclevel, "noAuthNoPriv");
+	/* Need checks to verify seclevel and authproto choices */
 
+	/* default protocol is set in variable declaraion, so this can't
+	 * possibly be NULL any-more. It can, however, be a zero length string
+	 * (if a check_command is specified that can use either v1 or v2c, the
+	 * $ARGx$ macro is quote-escaped and not given in service-description)
+	 * in which case we don't fuss much about it but just set it to default */
+	if (!strlen(proto))
+		proto = DEFAULT_PROTOCOL;
 
-	if (authproto == NULL ) 
-		asprintf(&authproto, DEFAULT_AUTH_PROTOCOL);
-	
-	 
-	
-	if (proto == NULL || (strcmp(proto,DEFAULT_PROTOCOL) == 0) ) {        /* default protocol version */
-		asprintf(&proto, DEFAULT_PROTOCOL);
+	if (proto[0] == '1' || proto[0] == '2') {   /* community based access */
 		asprintf(&authpriv, "%s%s", "-c ", community);
 	}
 	else if ( strcmp (proto, "3") == 0 ) {                 /* snmpv3 args */
-		asprintf(&proto, "%s", "3");
-		
+		proto = "3";
+
 		if ( (strcmp(seclevel, "noAuthNoPriv") == 0) || seclevel == NULL ) {
-			asprintf(&authpriv, "%s", "-l noAuthNoPriv" );
+			asprintf(&authpriv, "%s %s", "-l", DEFAULT_SEC_LEVEL);
 		}
 		else if ( strcmp(seclevel, "authNoPriv") == 0 ) {
 			if ( secname == NULL || authpasswd == NULL) {
-				printf (_("Missing secname (%s) or authpassword (%s) ! \n"),secname, authpasswd );
+				printf (_("Missing secname or authpassword!\n"));
 				print_usage ();
 				exit (STATE_UNKNOWN);
 			}
@@ -662,7 +658,7 @@
 		}
 		else if ( strcmp(seclevel, "authPriv") == 0 ) {
 			if ( secname == NULL || authpasswd == NULL || privpasswd == NULL ) {
-				printf (_("Missing secname (%s), authpassword (%s), or privpasswd (%s)! \n"),secname, authpasswd,privpasswd );
+				printf (_("Missing secname, authpassword or privpasswd!\n"));
 				print_usage ();
 				exit (STATE_UNKNOWN);
 			}