diff --git a/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgCGIServlet.java b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgCGIServlet.java
index e116aafcc5..a87e4c27c7 100644
--- a/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgCGIServlet.java
+++ b/scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgCGIServlet.java
@@ -49,6 +49,7 @@ import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryProvider;
 import sonia.scm.repository.RepositoryRequestListenerUtil;
 import sonia.scm.util.AssertUtil;
+import sonia.scm.util.Util;
 import sonia.scm.web.cgi.CGIExecutor;
 import sonia.scm.web.cgi.CGIExecutorFactory;
 import sonia.scm.web.cgi.EnvList;
@@ -86,6 +87,9 @@ public class HgCGIServlet extends HttpServlet
   /** Field description */
   public static final String ENV_SESSION_PREFIX = "SCM_";
 
+  /** Field description */
+  public static final String SCM_CREDENTIALS = "SCM_CREDENTIALS";
+
   /** Field description */
   private static final long serialVersionUID = -3492811300905099810L;
 
@@ -191,6 +195,12 @@ public class HgCGIServlet extends HttpServlet
         env.set(key, session.getAttribute(key).toString());
       }
     }
+
+    // issue-97
+    if (!env.containsKey(SCM_CREDENTIALS))
+    {
+      env.set(SCM_CREDENTIALS, Util.EMPTY_STRING);
+    }
   }
 
   /**