diff -ruN mysql-5.1.39.orig/storage/ndb/include/util/SocketServer.hpp mysql-5.1.39/storage/ndb/include/util/SocketServer.hpp
--- mysql-5.1.39.orig/storage/ndb/include/util/SocketServer.hpp 2009-10-13 15:43:50.000000000 +0200
+++ mysql-5.1.39/storage/ndb/include/util/SocketServer.hpp      2009-10-13 15:44:10.000000000 +0200
@@ -122,7 +122,7 @@
   MutexVector<ServiceInstance> m_services;
   unsigned m_maxSessions;

-  void doAccept();
+  bool doAccept();
   void checkSessionsImpl();
   void startSession(SessionInstance &);

diff -ruN mysql-5.1.39.orig/storage/ndb/src/common/util/SocketServer.cpp mysql-5.1.39/storage/ndb/src/common/util/SocketServer.cpp
--- mysql-5.1.39.orig/storage/ndb/src/common/util/SocketServer.cpp      2009-10-13 15:39:46.000000000 +0200
+++ mysql-5.1.39/storage/ndb/src/common/util/SocketServer.cpp   2009-10-13 15:51:32.000000000 +0200
@@ -152,7 +152,7 @@
   DBUG_RETURN(true);
 }

-void
+bool
 SocketServer::doAccept(){
   fd_set readSet, exceptionSet;
   FD_ZERO(&readSet);
@@ -177,7 +177,8 @@
       if(FD_ISSET(si.m_socket, &readSet)){
        NDB_SOCKET_TYPE childSock = accept(si.m_socket, 0, 0);
        if(childSock == NDB_INVALID_SOCKET){
-         continue;
+         m_services.unlock();
+          return false;
        }

        SessionInstance s;
@@ -196,11 +197,14 @@

       if(FD_ISSET(si.m_socket, &exceptionSet)){
        DEBUG("socket in the exceptionSet");
-       continue;
+       m_services.unlock();
+        return false;
       }
     }
   }
   m_services.unlock();
+  return true;
+
 }

 extern "C"
@@ -244,11 +248,16 @@
   while(!m_stopThread){
     m_session_mutex.lock();
     checkSessionsImpl();
-    if(m_sessions.size() < m_maxSessions){
-      m_session_mutex.unlock();
-      doAccept();
-    } else {
-      m_session_mutex.unlock();
+    m_session_mutex.unlock();
+    
+    if(m_sessions.size() >= m_maxSessions){
+      // Don't accept more connections yet
+      NdbSleep_MilliSleep(200);
+      continue;
+    }
+
+    if (!doAccept()){
+      // accept failed, step back
       NdbSleep_MilliSleep(200);
     }
   }
diff -ruN mysql-5.1.39.orig/storage/ndb/test/ndbapi/testMgm.cpp mysql-5.1.39/storage/ndb/test/ndbapi/testMgm.cpp
--- mysql-5.1.39.orig/storage/ndb/test/ndbapi/testMgm.cpp       2009-10-13 15:39:43.000000000 +0200
+++ mysql-5.1.39/storage/ndb/test/ndbapi/testMgm.cpp    2009-10-13 16:29:28.000000000 +0200
@@ -787,6 +787,59 @@
   return result;
 }

+int runTestBug45497(NDBT_Context* ctx, NDBT_Step* step)
+{
+  int result = NDBT_OK;
+  int loops = ctx->getNumLoops();
+  Vector<NdbMgmd*> mgmds;
+
+  while(true)
+  {
+    NdbMgmd* mgmd = new NdbMgmd();
+
+    // Set quite short timeout
+    if (!mgmd->set_timeout(1000))
+    {
+      result = NDBT_FAILED;
+      break;
+    }
+
+    if (mgmd->connect())
+    {
+      mgmds.push_back(mgmd);
+      g_info << "connections: " << mgmds.size() << endl;
+      continue;
+    }
+
+   g_err << "Failed to make another connection, connections: "
+          << mgmds.size() << endl;
+
+
+    // Disconnect some connections
+    int to_disconnect = 10;
+    while(mgmds.size() && to_disconnect--)
+    {
+      g_info << "disconnnect, connections: " << mgmds.size() << endl;
+      NdbMgmd* mgmd = mgmds[0];
+      NdbMgmd* mgmd = mgmds[0];
+      mgmds.erase(0);
+      delete mgmd;
+    }
+
+    if (loops-- == 0)
+      break;
+  }
+
+  while(mgmds.size())
+  {
+    NdbMgmd* mgmd = mgmds[0];
+    mgmds.erase(0);
+    delete mgmd;
+  }
+
+  return result;
+}
+
+
 NDBT_TESTSUITE(testMgm);
 TESTCASE("SingleUserMode",
         "Test single user mode"){
@@ -828,6 +881,12 @@
   INITIALIZER(runTestMgmApiStructEventTimeout);

 }
+
+TESTCASE("Bug45497",
+         "Connect to ndb_mgmd until it can't handle more connections"){
+  STEP(runTestBug45497);
+}
+
 NDBT_TESTSUITE_END(testMgm);

 int main(int argc, const char** argv){
@@ -836,3 +895,5 @@
   return testMgm.execute(argc, argv);
 }

+template class Vector<NdbMgmd*>;
+