Rewording, use the more common multi-threaded/single-threaded.

doc/src/sgml/ecpg.sgml

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-$PostgreSQL: pgsql/doc/src/sgml/ecpg.sgml,v 1.68 2005/10/13 17:46:18 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ecpg.sgml,v 1.69 2005/10/13 17:55:18 momjian Exp $
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 <chapter id="ecpg">
@@ -1613,8 +1613,9 @@ ECPG = ecpg
     compiled with different flags, this function call will crash the 
     application because the internal representation of the 
     <literal>FILE</> pointers differ.  Specifically,
-    threading/non-threading, release/debug, and static/dynamic flags should 
-    be the same for the library and all applications using that library.
+    multi-threaded/single-threaded, release/debug, and static/dynamic 
+    flags should be the same for the library and all applications using
+    that library.
     </para>
     </note>
    </listitem>

doc/src/sgml/libpq.sgml

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-$PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.192 2005/10/13 17:46:18 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.193 2005/10/13 17:55:18 momjian Exp $
 -->
 
  <chapter id="libpq">
@@ -3520,9 +3520,9 @@ void PQtrace(PGconn *conn, FILE *stream);
 On Win32, if the <application>libpq</> library and an application are
 compiled with different flags, this function call will crash the 
 application because the internal representation of the <literal>FILE</> 
-pointers differ.  Specifically, threading/non-threading, release/debug, and
-static/dynamic flags should be the same for the library and all applications
-using that library.
+pointers differ.  Specifically, multi-threaded/single-threaded,
+release/debug, and static/dynamic flags should be the same for the
+library and all applications using that library.
 </para>
 </note>
 </listitem>