diff --git a/dom/plugins/base/nsPluginsDirUnix.cpp b/dom/plugins/base/nsPluginsDirUnix.cpp
index 698f5d22ce0..3e242f2e541 100644
--- a/dom/plugins/base/nsPluginsDirUnix.cpp
+++ b/dom/plugins/base/nsPluginsDirUnix.cpp
@@ -307,6 +307,10 @@ nsresult nsPluginFile::LoadPlugin(PRLibrary **outLibrary)
     printf("LoadPlugin() %s returned %lx\n", 
            libSpec.value.pathname, (unsigned long)pLibrary);
 #endif
+
+    if (!pLibrary) {
+        return NS_ERROR_FAILURE;
+    }
     
     return NS_OK;
 }
diff --git a/dom/plugins/ipc/PluginModuleChild.cpp b/dom/plugins/ipc/PluginModuleChild.cpp
index 52b027a77ce..029b81551c3 100644
--- a/dom/plugins/ipc/PluginModuleChild.cpp
+++ b/dom/plugins/ipc/PluginModuleChild.cpp
@@ -182,8 +182,9 @@ PluginModuleChild::Init(const std::string& aPluginFilename,
     if (!mLibrary)
 #endif
     {
-        DebugOnly<nsresult> rv = pluginFile.LoadPlugin(&mLibrary);
-        NS_ASSERTION(NS_OK == rv, "trouble with mPluginFile");
+        nsresult rv = pluginFile.LoadPlugin(&mLibrary);
+        if (NS_FAILED(rv))
+            return false;
     }
     NS_ASSERTION(mLibrary, "couldn't open shared object");