Index: apps/app_addon_sql_mysql.c
===================================================================
--- apps/app_addon_sql_mysql.c	(revision 915)
+++ apps/app_addon_sql_mysql.c	(working copy)
@@ -38,9 +38,12 @@
 #include <asterisk/lock.h>
 #include <asterisk/options.h>
 #include <asterisk/app.h>
+#include <asterisk/config.h>
 
 #define EXTRA_LOG 0
 
+int nullasstring = 1;
+
 static char *app = "MYSQL";
 
 static char *synopsis = "Do several mySQLy things";
@@ -85,6 +88,7 @@
 
 AST_MUTEX_DEFINE_STATIC(_mysql_mutex);
 
+#define MYSQL_CONFIG "mysql.conf"
 #define AST_MYSQL_ID_DUMMY   0
 #define AST_MYSQL_ID_CONNID  1
 #define AST_MYSQL_ID_RESID   2
@@ -392,7 +396,12 @@
 						break;
 					}
 					s6 = mysqlrow[j];
-					pbx_builtin_setvar_helper(chan, s5, s6 ? s6 : "NULL");
+
+					if (nullasstring) {
+						pbx_builtin_setvar_helper(chan, s5, s6 ? s6 : "NULL");
+					} else {
+						pbx_builtin_setvar_helper(chan, s5, s6);
+					}
 				}
 				ast_debug(5, "ast_MYSQL_fetch: numFields=%d\n", numFields);
 				set_asterisk_int(chan, args.resultvar, 1); // try more rows
@@ -496,6 +505,24 @@
 static int load_module(void)
 {
 	struct MYSQLidshead *headp = &_mysql_ids_head;
+	struct ast_flags config_flags = { 0 };
+	struct ast_config *cfg = ast_config_load(MYSQL_CONFIG, config_flags);
+	const char *temp;
+
+	if (!cfg) {
+		ast_log(LOG_NOTICE, "MySQL config file %s not found. MySQL will return NULL as 'NULL' string.\n", MYSQL_CONFIG);
+	} else {
+	
+		temp = ast_variable_retrieve(cfg, "general", "nullasstring");
+	
+		if (ast_true(temp)) {
+			ast_log(LOG_NOTICE, "MySQL will return NULL as 'NULL' string.\n");
+		} else { 
+			ast_log(LOG_NOTICE, "MySQL will return NULL as NULL.\n");
+			nullasstring = 0;
+		}
+	}
+
 	AST_LIST_HEAD_INIT(headp);
 	return ast_register_application(app, MYSQL_exec, synopsis, descrip);
 }