diff --git a/src/core/scheduler.cpp b/src/core/scheduler.cpp
--- a/src/core/scheduler.cpp
+++ b/src/core/scheduler.cpp
@@ -129,6 +129,11 @@
     return false;
 }
 
+void SlaveKeeper::clear()
+{
+    m_idleSlaves.clear();
+}
+
 QList<Slave *> SlaveKeeper::allSlaves() const
 {
     return m_idleSlaves.values();
@@ -404,6 +409,7 @@
 
 ProtoQueue::~ProtoQueue()
 {
+    m_slaveKeeper.clear();
     Q_FOREACH (Slave *slave, allSlaves()) {
         // kill the slave process, then remove the interface in our process
         slave->kill();
diff --git a/src/core/scheduler_p.h b/src/core/scheduler_p.h
--- a/src/core/scheduler_p.h
+++ b/src/core/scheduler_p.h
@@ -25,6 +25,7 @@
 namespace KIO
 {
 
+// The slave keeper manages the list of idle slaves that can be reused
 class SlaveKeeper : public QObject
 {
     Q_OBJECT
@@ -37,6 +38,8 @@
     KIO::Slave *takeSlaveForJob(KIO::SimpleJob *job);
     // remove slave from keeper
     bool removeSlave(KIO::Slave *slave);
+    // remove all slaves from keeper
+    void clear();
     QList<KIO::Slave *> allSlaves() const;
 
 private:
diff --git a/src/core/slave.cpp b/src/core/slave.cpp
--- a/src/core/slave.cpp
+++ b/src/core/slave.cpp
@@ -300,7 +300,7 @@
     if (!d->m_refCount) {
         d->connection->disconnect(this);
         this->disconnect();
-        deleteLater();
+        delete this; // yes it reads funny, but it's too late for a deleteLater() here, no event loop anymore
     }
 }