--- loginutils/adduser.c.orig
+++ loginutils/adduser.c
@@ -44,6 +44,7 @@
 //usage:     "\n	-H		Don't create home directory"
 //usage:     "\n	-u UID		User id"
 //usage:     "\n	-k SKEL		Skeleton directory (/etc/skel)"
+//usage:     "\n	-b DOB		Date of birth (YYYYMMDD)"
 
 #include "libbb.h"
 
@@ -61,6 +62,7 @@
 #define OPT_DONT_MAKE_HOME (1 << 6)
 #define OPT_UID            (1 << 7)
 #define OPT_SKEL           (1 << 8)
+#define OPT_DOB            (1 << 9)
 
 /* remix */
 /* recoded such that the uid may be passed in *p */
@@ -128,6 +130,7 @@
 		"no-create-home\0"      No_argument       "H"
 		"uid\0"                 Required_argument "u"
 		"skel\0"                Required_argument "k"
+		"dob\0"                 Required_argument "b"
 		;
 
 /*
@@ -141,6 +144,7 @@
 	unsigned opts;
 	char *uid;
 	const char *skel = "/etc/skel";
+	char *dob = NULL;
 
 	/* got root? */
 	if (geteuid()) {
@@ -151,12 +155,12 @@
 	pw.pw_dir = NULL;
 
 	opts = getopt32long(argv, "^"
-			"h:g:s:G:DSHu:k:"
+			"h:g:s:G:DSHu:k:b:"
 			/* at least one and at most two non-option args */
 			/* disable interactive passwd for system accounts */
 			"\0" "-1:?2:SD",
 			adduser_longopts,
-			&pw.pw_dir, &pw.pw_gecos, &pw.pw_shell,
-			&usegroup, &uid, &skel
+			&pw.pw_dir, &pw.pw_gecos, &pw.pw_shell,
+			&usegroup, &uid, &skel, &dob
 	);
 	if (opts & OPT_UID)
@@ -200,6 +204,16 @@
 		free(p);
 #endif
 
+	/* Record date of birth if specified */
+	if (opts & OPT_DOB) {
+		FILE *f = fopen("/etc/birthdays", "a");
+		if (f) {
+			fprintf(f, "%s:x:%s:\n", pw.pw_name, dob);
+			fclose(f);
+		} else {
+			bb_perror_msg("/etc/birthdays");
+		}
+	}
+
 	/* add to group */
 	addgroup_wrapper(&pw, usegroup);