diff --git a/mozilla/xpcom/components/nsComponentManager.cpp b/mozilla/xpcom/components/nsComponentManager.cpp
index 168d364c62c..9265389b0c5 100644
--- a/mozilla/xpcom/components/nsComponentManager.cpp
+++ b/mozilla/xpcom/components/nsComponentManager.cpp
@@ -217,6 +217,9 @@ nsGetServiceFromCategory::operator()(const nsIID& aIID, void** aInstancePtr) con
 {
     nsresult rv;
     nsXPIDLCString value;
+    nsCOMPtr<nsIServiceManager> serviceManager =
+        do_QueryInterface(mServiceManager);
+    // XXX Should we use the provided service manager?
     nsCOMPtr<nsICategoryManager> catman =
         do_GetService(kCategoryManagerCID, &rv);
     if (NS_FAILED(rv)) goto error;
@@ -233,8 +236,8 @@ nsGetServiceFromCategory::operator()(const nsIID& aIID, void** aInstancePtr) con
         rv = NS_ERROR_SERVICE_NOT_AVAILABLE;
         goto error;
     }
-    if (mServiceManager) {
-        rv = mServiceManager->GetServiceByContractID(value, aIID, (void**)aInstancePtr);
+    if (serviceManager) {
+        rv = serviceManager->GetServiceByContractID(value, aIID, (void**)aInstancePtr);
     } else {
         nsCOMPtr<nsIServiceManager> mgr;
         NS_GetServiceManager(getter_AddRefs(mgr));
diff --git a/mozilla/xpcom/components/nsIServiceManagerUtils.h b/mozilla/xpcom/components/nsIServiceManagerUtils.h
index b225b6a2e8d..5e3ac6885b0 100644
--- a/mozilla/xpcom/components/nsIServiceManagerUtils.h
+++ b/mozilla/xpcom/components/nsIServiceManagerUtils.h
@@ -49,7 +49,7 @@ class NS_COM nsGetServiceByCID : public nsCOMPtr_helper
  public:
     nsGetServiceByCID( const nsCID& aCID, nsISupports* aServiceManager, nsresult* aErrorPtr )
         : mCID(aCID),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -59,7 +59,7 @@ class NS_COM nsGetServiceByCID : public nsCOMPtr_helper
     
  private:
     const nsCID&                mCID;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };
 
@@ -82,7 +82,7 @@ class NS_COM nsGetServiceByContractID : public nsCOMPtr_helper
  public:
     nsGetServiceByContractID( const char* aContractID, nsISupports* aServiceManager, nsresult* aErrorPtr )
         : mContractID(aContractID),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -92,7 +92,7 @@ class NS_COM nsGetServiceByContractID : public nsCOMPtr_helper
     
  private:
     const char*                 mContractID;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };
 
@@ -118,7 +118,7 @@ class nsGetServiceFromCategory : public nsCOMPtr_helper
                              nsresult* aErrorPtr)
         : mCategory(aCategory),
         mEntry(aEntry),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -128,7 +128,7 @@ class nsGetServiceFromCategory : public nsCOMPtr_helper
  protected:
     const char*                 mCategory;
     const char*                 mEntry;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };
 
diff --git a/mozilla/xpcom/glue/nsComponentManagerUtils.cpp b/mozilla/xpcom/glue/nsComponentManagerUtils.cpp
index 3be62fc86a1..42ffafa7d0f 100644
--- a/mozilla/xpcom/glue/nsComponentManagerUtils.cpp
+++ b/mozilla/xpcom/glue/nsComponentManagerUtils.cpp
@@ -150,8 +150,10 @@ nsresult
 nsGetServiceByCID::operator()( const nsIID& aIID, void** aInstancePtr ) const
 {
     nsresult status = NS_ERROR_FAILURE;
-    if ( mServiceManager ) {
-        status = mServiceManager->GetService(mCID, aIID, (void**)aInstancePtr);
+    nsCOMPtr<nsIServiceManager> serviceManager =
+        do_QueryInterface(mServiceManager);
+    if ( serviceManager ) {
+        status = serviceManager->GetService(mCID, aIID, (void**)aInstancePtr);
     } else {
         nsCOMPtr<nsIServiceManager> mgr;
         NS_GetServiceManager(getter_AddRefs(mgr));
@@ -170,8 +172,10 @@ nsresult
 nsGetServiceByContractID::operator()( const nsIID& aIID, void** aInstancePtr ) const
 {
     nsresult status = NS_ERROR_FAILURE;
-    if ( mServiceManager ) {
-        status = mServiceManager->GetServiceByContractID(mContractID, aIID, (void**)aInstancePtr);
+    nsCOMPtr<nsIServiceManager> serviceManager =
+        do_QueryInterface(mServiceManager);
+    if ( serviceManager ) {
+        status = serviceManager->GetServiceByContractID(mContractID, aIID, (void**)aInstancePtr);
     } else {
         nsCOMPtr<nsIServiceManager> mgr;
         NS_GetServiceManager(getter_AddRefs(mgr));
diff --git a/mozilla/xpcom/glue/nsServiceManagerUtils.h b/mozilla/xpcom/glue/nsServiceManagerUtils.h
index b225b6a2e8d..5e3ac6885b0 100644
--- a/mozilla/xpcom/glue/nsServiceManagerUtils.h
+++ b/mozilla/xpcom/glue/nsServiceManagerUtils.h
@@ -49,7 +49,7 @@ class NS_COM nsGetServiceByCID : public nsCOMPtr_helper
  public:
     nsGetServiceByCID( const nsCID& aCID, nsISupports* aServiceManager, nsresult* aErrorPtr )
         : mCID(aCID),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -59,7 +59,7 @@ class NS_COM nsGetServiceByCID : public nsCOMPtr_helper
     
  private:
     const nsCID&                mCID;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };
 
@@ -82,7 +82,7 @@ class NS_COM nsGetServiceByContractID : public nsCOMPtr_helper
  public:
     nsGetServiceByContractID( const char* aContractID, nsISupports* aServiceManager, nsresult* aErrorPtr )
         : mContractID(aContractID),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -92,7 +92,7 @@ class NS_COM nsGetServiceByContractID : public nsCOMPtr_helper
     
  private:
     const char*                 mContractID;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };
 
@@ -118,7 +118,7 @@ class nsGetServiceFromCategory : public nsCOMPtr_helper
                              nsresult* aErrorPtr)
         : mCategory(aCategory),
         mEntry(aEntry),
-        mServiceManager( do_QueryInterface(aServiceManager) ),
+        mServiceManager(aServiceManager),
         mErrorPtr(aErrorPtr)
         {
             // nothing else to do
@@ -128,7 +128,7 @@ class nsGetServiceFromCategory : public nsCOMPtr_helper
  protected:
     const char*                 mCategory;
     const char*                 mEntry;
-    nsCOMPtr<nsIServiceManager> mServiceManager;
+    nsISupports*                mServiceManager;
     nsresult*                   mErrorPtr;
 };