Index: funcs/func_env.c
===================================================================
--- funcs/func_env.c	(revision 219061)
+++ funcs/func_env.c	(working copy)
@@ -44,6 +44,7 @@
 			</parameter>
 		</syntax>
 		<description>
+			Variables starting with <literal>AST_</literal> are reserved to the system and may not be set.
 		</description>
 	</function>
 	<function name="STAT" language="en_US">
@@ -106,7 +107,7 @@
 static int env_write(struct ast_channel *chan, const char *cmd, char *data,
 		     const char *value)
 {
-	if (!ast_strlen_zero(data)) {
+	if (!ast_strlen_zero(data) && strncmp(data, "AST_", 4)) {
 		if (!ast_strlen_zero(value)) {
 			setenv(data, value, 1);
 		} else {
Index: main/asterisk.c
===================================================================
--- main/asterisk.c	(revision 219061)
+++ main/asterisk.c	(working copy)
@@ -3091,6 +3091,18 @@
 	ast_config_destroy(cfg);
 }
 
+static void env_init(void)
+{
+	setenv("AST_SYSTEMNAME", ast_config_AST_SYSTEM_NAME, 1);
+	setenv("AST_BUILD_HOST", ast_build_hostname, 1);
+	setenv("AST_BUILD_DATE", ast_build_date, 1);
+	setenv("AST_BUILD_KERNEL", ast_build_kernel, 1);
+	setenv("AST_BUILD_MACHINE", ast_build_machine, 1);
+	setenv("AST_BUILD_OS", ast_build_os, 1);
+	setenv("AST_BUILD_USER", ast_build_user, 1);
+	setenv("AST_VERSION", ast_get_version(), 1);
+}
+
 int main(int argc, char *argv[])
 {
 	int c;
@@ -3268,6 +3280,7 @@
 	}
 
 	ast_readconfig();
+	env_init();
 
 	if (ast_opt_remote && remotesock != NULL)
 		ast_copy_string((char *) cfg_paths.socket_path, remotesock, sizeof(cfg_paths.socket_path));