diff --git a/lib/config.js b/lib/config.js
index <HASH>..<HASH> 100644
--- a/lib/config.js
+++ b/lib/config.js
@@ -64,9 +64,9 @@ function importEnvVars(collection, envPrefix) {
         envValue = process.env[envKey];
     if ((typeof(value) == 'number') || (typeof(value) == 'string') || (typeof(value) == 'boolean') || (value == null)) {
       if (envValue && typeof(envValue == 'string')) {
-        if (envValue.match(/\s*(true|on)\s*/i)) {
+        if (envValue.match(/^\s*(true|on)\s*$/i)) {
           envValue = true;
-        } else if (envValue.match(/\s*(false|off)\s*/i)) {
+        } else if (envValue.match(/^\s*(false|off)\s*$/i)) {
           envValue = false;
         }
         collection[key] = envValue;
@@ -79,4 +79,4 @@ function importEnvVars(collection, envPrefix) {
 }
 importEnvVars(config, 'JSBIN');
 
-module.exports = config;
\ No newline at end of file
+module.exports = config;
Make the config environment variable override mechanism support environment variables that contain true/on or false/off.