Add index mention:

<P>In pre-8.0 releases, indexes often can not be used unless the data
    types exactly match the index's column types.  This is particularly
    true of int2, int8, and numeric column indexes.</P>

doc/FAQ

@@ -1,7 +1,7 @@
 
                 Frequently Asked Questions (FAQ) for PostgreSQL
                                        
-   Last updated: Wed Aug 25 23:18:13 EDT 2004
+   Last updated: Tue Aug 31 23:28:02 EDT 2004
    
    Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
    
@@ -797,6 +797,10 @@
        section 4.12.
      * The default C locale must be used during initdb.
        
+   In pre-8.0 releases, indexes often can not be used unless the data
+   types exactly match the index's column types. This is particularly
+   true of int2, int8, and numeric column indexes.
+   
     4.9) How do I see how the query optimizer is evaluating my query?
     
    See the EXPLAIN manual page.

doc/src/FAQ/FAQ.html

@@ -10,7 +10,7 @@
   alink="#0000ff">
     <H1>Frequently Asked Questions (FAQ) for PostgreSQL</H1>
 
-    <P>Last updated: Wed Aug 25 23:18:13 EDT 2004</P>
+    <P>Last updated: Tue Aug 31 23:28:02 EDT 2004</P>
 
     <P>Current maintainer: Bruce Momjian (<A href=
     "mailto:pgman@candle.pha.pa.us">pgman@candle.pha.pa.us</A>)<BR>
@@ -1001,6 +1001,10 @@
     </UL>
     <P>
 
+    <P>In pre-8.0 releases, indexes often can not be used unless the data
+    types exactly match the index's column types.  This is particularly
+    true of int2, int8, and numeric column indexes.</P>
+
     <H4><A name="4.9">4.9</A>) How do I see how the query optimizer is
     evaluating my query?</H4>