diff -ruN ssmtp-original/ssmtp.c ssmtp-fixed/ssmtp.c
--- ssmtp-original/ssmtp.c	2008-08-10 18:26:33.000000000 +0200
+++ ssmtp-fixed/ssmtp.c	2008-08-10 19:38:22.000000000 +0200
@@ -55,21 +55,21 @@
 
 #define ARPADATE_LENGTH 32		/* Current date in RFC format */
 char arpadate[ARPADATE_LENGTH];
-char *auth_user = (char)NULL;
-char *auth_pass = (char)NULL;
-char *auth_method = (char)NULL;		/* Mechanism for SMTP authentication */
-char *mail_domain = (char)NULL;
-char *from = (char)NULL;		/* Use this as the From: address */
+char *auth_user = (char *)NULL;
+char *auth_pass = (char *)NULL;
+char *auth_method = (char *)NULL;		/* Mechanism for SMTP authentication */
+char *mail_domain = (char *)NULL;
+char *from = (char *)NULL;		/* Use this as the From: address */
 char *hostname;
 char *mailhost = "mailhub";
-char *minus_f = (char)NULL;
-char *minus_F = (char)NULL;
+char *minus_f = (char *)NULL;
+char *minus_F = (char *)NULL;
 char *gecos;
-char *prog = (char)NULL;
+char *prog = (char *)NULL;
 char *root = NULL;
 char *tls_cert = "/etc/ssl/certs/ssmtp.pem";	/* Default Certificate */
-char *uad = (char)NULL;
-char *config_file = (char)NULL;		/* alternate configuration file */
+char *uad = (char *)NULL;
+char *config_file = (char *)NULL;		/* alternate configuration file */
 
 headers_t headers, *ht;
 
@@ -261,7 +261,7 @@
 
 	p = (str + strlen(str));
 	while(isspace(*--p)) {
-		*p = (char)NULL;
+		*p = '\0';
 	}
 
 	return(p);
@@ -287,7 +287,7 @@
 		q++;
 
 		if((p = strchr(q, '>'))) {
-			*p = (char)NULL;
+			*p = '\0';
 		}
 
 #if 0
@@ -310,7 +310,7 @@
 	q = strip_post_ws(p);
 	if(*q == ')') {
 		while((*--q != '('));
-		*q = (char)NULL;
+		*q = '\0';
 	}
 	(void)strip_post_ws(p);
 
@@ -353,7 +353,7 @@
 	char *p;
 
 	if((p = strchr(str, '\n'))) {
-		*p = (char)NULL;
+		*p = '\0';
 	}
 
 	/* Any line beginning with a dot has an additional dot inserted;
@@ -386,7 +386,7 @@
 		while(fgets(buf, sizeof(buf), fp)) {
 			/* Make comments invisible */
 			if((p = strchr(buf, '#'))) {
-				*p = (char)NULL;
+				*p = '\0';
 			}
 
 			/* Ignore malformed lines and comments */
@@ -485,6 +485,11 @@
 				die("from_format() -- snprintf() failed");
 			}
 		}
+		else {
+			if(snprintf(buf, BUF_SZ, "%s", str) == -1) {
+				die("from_format() -- snprintf() failed");
+			}
+		}
 	}
 
 #if 0
@@ -516,7 +521,7 @@
 #endif
 
 	/* Ignore missing usernames */
-	if(*str == (char)NULL) {
+	if(*str == '\0') {
 		return;
 	}
 
@@ -573,7 +578,7 @@
 		}
 
 		/* End of string? */
-		if(*(q + 1) == (char)NULL) {
+		if(*(q + 1) == '\0') {
 			got_addr = True;
 		}
 
@@ -581,7 +586,7 @@
 		if((*q == ',') && (in_quotes == False)) {
 			got_addr = True;
 
-			*q = (char)NULL;
+			*q = '\0';
 		}
 
 		if(got_addr) {
@@ -673,7 +678,7 @@
 	if(strncasecmp(ht->string, "From:", 5) == 0) {
 #if 1
 		/* Hack check for NULL From: line */
-		if(*(p + 6) == (char)NULL) {
+		if(*(p + 6) == '\0') {
 			return;
 		}
 #endif
@@ -738,7 +743,7 @@
 	size_t size = BUF_SZ, len = 0;
 	char *p = (char *)NULL, *q;
 	bool_t in_header = True;
-	char l = (char)NULL;
+	char l = '\0';
 	int c;
 
 	while(in_header && ((c = fgetc(stream)) != EOF)) {
@@ -773,9 +778,9 @@
 						in_header = False;
 
 				default:
-						*q = (char)NULL;
+						*q = '\0';
 						if((q = strrchr(p, '\n'))) {
-							*q = (char)NULL;
+							*q = '\0';
 						}
 						header_save(p);
 
@@ -806,9 +811,9 @@
 						in_header = False;
 
 				default:
-						*q = (char)NULL;
+						*q = '\0';
 						if((q = strrchr(p, '\n'))) {
-							*q = (char)NULL;
+							*q = '\0';
 						}
 						header_save(p);
 
@@ -882,7 +887,7 @@
 		char *rightside;
 		/* Make comments invisible */
 		if((p = strchr(buf, '#'))) {
-			*p = (char)NULL;
+			*p = '\0';
 		}
 
 		/* Ignore malformed lines and comments */
@@ -1301,7 +1306,7 @@
 	int i = 0;
 	char c;
 
-	while((i < size) && (fd_getc(fd, &c) == 1)) {
+	while((i < size - 1) && (fd_getc(fd, &c) == 1)) {
 		if(c == '\r');	/* Strip <CR> */
 		else if(c == '\n') {
 			break;
@@ -1310,7 +1315,7 @@
 			buf[i++] = c;
 		}
 	}
-	buf[i] = (char)NULL;
+	buf[i] = '\0';
 
 	return(buf);
 }
@@ -1723,7 +1728,7 @@
 		j = 0;
 
 		add = 1;
-		while(argv[i][++j] != (char)NULL) {
+		while(argv[i][++j] != '\0') {
 			switch(argv[i][j]) {
 #ifdef INET6
 			case '6':