diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2cf8ac82..4ac7c97c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,9 @@
 All notable changes to the Zlux Server Framework package will be documented in this file.
 This repo is part of the app-server Zowe Component, and the change logs here may appear on Zowe.org in that section.
 
+## 3.1.0
+- Fix: Server would not work when API Gateway token name was customized (#573)
+
 ## 3.0.0
 - Enhancement: Add ability for server to dynamically load plugin web content based on `entryPoint` specification in the
 `pluginDefinition.json`
diff --git a/plugins/sso-auth/lib/apimlHandler.js b/plugins/sso-auth/lib/apimlHandler.js
index 18da936b..9977f324 100644
--- a/plugins/sso-auth/lib/apimlHandler.js
+++ b/plugins/sso-auth/lib/apimlHandler.js
@@ -21,7 +21,6 @@ const zluxUtil = require('../../../lib/util');
  */
 const DEFAULT_EXPIRATION_MS = 29700000;
 const TOKEN_NAME = 'apimlAuthenticationToken';
-const TOKEN_LENGTH = TOKEN_NAME.length;
 
 function readUtf8FilesToArray(fileArray) {
   var contentArray = [];
@@ -57,6 +56,11 @@ function readUtf8FilesToArray(fileArray) {
 class ApimlHandler {
   constructor(pluginDef, pluginConf, componentConf, context, zoweConf) {
     this.logger = context.logger;    
+    if (zoweConf.zowe.cookieIdentifier && (zoweConf.components.gateway?.apiml?.security?.auth?.uniqueCookie === true)) {
+      this.tokenName = `${TOKEN_NAME}.${zoweConf.zowe.cookieIdentifier}`;
+    } else {
+      this.tokenName = TOKEN_NAME;
+    }
     this.apimlConf = componentConf.node.mediationLayer.server;    
     this.gatewayUrl = `https://${this.apimlConf.gatewayHostname}:${this.apimlConf.gatewayPort}`;
     this.isHttps = !zluxUtil.isClientAttls(zoweConf);
@@ -72,7 +76,7 @@ class ApimlHandler {
 
   logout(request, sessionState) {
     return new Promise((resolve, reject) => {
-      if (!(request.cookies && request.cookies[TOKEN_NAME])) {
+      if (!(request.cookies && request.cookies[this.tokenName])) {
         return resolve({success: true});
       }
       const gatewayUrl = this.gatewayUrl;
@@ -83,7 +87,7 @@ class ApimlHandler {
         path: '/apicatalog/api/v1/auth/logout',
         method: 'POST',
         headers: {
-          'apimlAuthenticationToken': request.cookies[TOKEN_NAME]
+          'apimlAuthenticationToken': request.cookies[this.tokenName]
         },
         agent: this.httpsAgent
       }
@@ -94,7 +98,7 @@ class ApimlHandler {
         res.on('end', () => {
           let apimlCookie;
           if (res.statusCode >= 200 && res.statusCode < 300) {
-            resolve({ success: true, cookies: [{name:TOKEN_NAME,
+            resolve({ success: true, cookies: [{name:this.tokenName,
                                                 value:'non-token',
                                                 options: {httpOnly: true,
                                                           secure: true,
@@ -153,7 +157,7 @@ class ApimlHandler {
           resolve({success: false}); // return the object directly
         });
       });
-    } else if (request.cookies && request.cookies[TOKEN_NAME]) {
+    } else if (request.cookies && request.cookies[this.tokenName]) {
       return this.authenticateViaCookie(request, sessionState);
     } else {
       return Promise.resolve({success: false});
@@ -162,8 +166,8 @@ class ApimlHandler {
 
   authenticateViaCookie(request, sessionState) {
     return new Promise((resolve, reject)=> {
-      this.logger.debug(`Authenticate with cookie`,TOKEN_NAME);
-      this.queryToken(request.cookies[TOKEN_NAME]).then(data=> {
+      this.logger.debug(`Authenticate with cookie`,this.tokenName);
+      this.queryToken(request.cookies[this.tokenName]).then(data=> {
         let expiration;
         const expirationDate = new Date(data.expiration);
         const creationDate = new Date(data.creation);
@@ -177,7 +181,7 @@ class ApimlHandler {
           this.doLogin(request, sessionState, true).then(result=> resolve(result))
             .catch(e => reject(e));
         } else {
-          this.setState(request.cookies[TOKEN_NAME],
+          this.setState(request.cookies[this.tokenName],
                         data.userId, sessionState);
           resolve({success: true, username: sessionState.username, expms: expiration});
         }
@@ -230,7 +234,7 @@ class ApimlHandler {
     return new Promise((resolve, reject) => {
       const options = this.makeOptions('/gateway/api/v1/auth/query',
                                        'GET',
-                                       TOKEN_NAME+'='+token);
+                                       this.tokenName+'='+token);
       
       let data = [];
       this.logger.debug(`Sending query token request to path=${options.path}`);
@@ -283,9 +287,9 @@ class ApimlHandler {
             if (typeof res.headers['set-cookie'] === 'object') {
               for (const cookie of res.headers['set-cookie']) {
                 const content = cookie.split(';')[0];
-                let index = content.indexOf(TOKEN_NAME);
+                let index = content.indexOf(this.tokenName);
                 if (index >= 0) {
-                  token = content.substring(index+1+TOKEN_LENGTH);
+                  token = content.substring(index+1+this.tokenName.length);
                 }
               }
             }
@@ -305,7 +309,7 @@ class ApimlHandler {
               if (expiration > 0) {
                 this.setState(token, data.userId, sessionState);
                 resolve({ success: true, username: sessionState.username, expms: expiration,
-                          cookies: [{name:TOKEN_NAME, value:token, options: {httpOnly: true, secure: true}}]});
+                          cookies: [{name:this.tokenName, value:token, options: {httpOnly: true, secure: true}}]});
               } else {
                 resolve({ success: false, reason: 'Unknown'});
               }
@@ -371,7 +375,7 @@ class ApimlHandler {
   authorized(request, sessionState) {
     if (sessionState.authenticated) {
       request.username = sessionState.username;
-      request.ssoToken = request.cookies[TOKEN_NAME];
+      request.ssoToken = request.cookies[this.tokenName];
       return Promise.resolve({ authenticated: true, authorized: true });
     } else {
       return Promise.resolve({ authenticated: false, authorized: false });
@@ -382,7 +386,7 @@ class ApimlHandler {
     if (!sessionState.apimlToken) {
       return;
     }
-//    req2Options.headers[TOKEN_NAME] = sessionState.apimlToken;
+//    req2Options.headers[this.tokenName] = sessionState.apimlToken;
     if (this.usingSso) {
       req2Options.headers['Authorization'] = 'Bearer '+sessionState.apimlToken;
     }
@@ -390,7 +394,7 @@ class ApimlHandler {
 
   restoreSessionState(request, sessionState) {
     return new Promise((resolve, _reject) => {
-      const token = request.cookies[TOKEN_NAME];
+      const token = request.cookies[this.tokenName];
       if (!token) {
         sessionState.authenticated = false;
         resolve({success: false});