diff --git a/src/dbd-oracle-dbi.lisp b/src/dbd-oracle-dbi.lisp
index c4d35ce..2739473 100644
--- a/src/dbd-oracle-dbi.lisp
+++ b/src/dbd-oracle-dbi.lisp
@@ -6,6 +6,9 @@
 
 (cl-syntax:use-syntax :annot)
 
+(unless *oracle-library-loaded*
+  (oracle-load-foreign))
+
 @export
 (defclass <dbd-oracle> (<dbi-driver>) ())
 
@@ -85,8 +88,6 @@ string conversion functions.
 Example of DATABASE-NAME:
   127.0.0.1:1521/orcl
 "
-  (unless *oracle-library-loaded*
-    (oracle-load-foreign))
   (make-instance '<dbd-oracle-connection>
      :database-name database-name
      :auto-commit nil
diff --git a/src/dbd-oracle.lisp b/src/dbd-oracle.lisp
index 6d87539..7ca455f 100644
--- a/src/dbd-oracle.lisp
+++ b/src/dbd-oracle.lisp
@@ -260,12 +260,12 @@ the length of that format.")
     (setf (deref-vp envhp) +null-void-pointer+)
 
     (progn
-      (oci-initialize +oci-object+ +null-void-pointer+ +null-void-pointer+
+      (oci-initialize +oci-threaded+ +null-void-pointer+ +null-void-pointer+
                       +null-void-pointer+ +null-void-pointer-pointer+)
       (ignore-errors (oci-handle-alloc +null-void-pointer+ envhp
                                        +oci-htype-env+ 0
                                        +null-void-pointer-pointer+)) ;no testing return
-      (oci-env-init envhp +oci-default+ 0 +null-void-pointer-pointer+))
+      (oci-env-init envhp +oci-threaded+ 0 +null-void-pointer-pointer+))
 
     (oci-handle-alloc (deref-vp envhp) errhp
                       +oci-htype-error+ 0 +null-void-pointer-pointer+)
diff --git a/src/foreign-resources.lisp b/src/foreign-resources.lisp
index 2dc910f..0d0fcb7 100644
--- a/src/foreign-resources.lisp
+++ b/src/foreign-resources.lisp
@@ -11,7 +11,8 @@
 
 (in-package #:dbd.oracle)
 
-(defparameter *foreign-resource-hash* (make-hash-table :test #'equal))
+(defparameter *foreign-resource-hash*
+  (make-hash-table :test #'equal :synchronized t))
 
 (defstruct (foreign-resource)
   (type (error "Missing TYPE.")