diff --git a/chapter01/changelog.xml b/chapter01/changelog.xml
index ea62810a2..3707b51e3 100644
--- a/chapter01/changelog.xml
+++ b/chapter01/changelog.xml
@@ -39,6 +39,9 @@
     <listitem>
       <para>March 18, 2006</para>
       <itemizedlist>
+        <listitem>
+          <para>[matthew] - Upgrade to flex-2.5.33.</para>
+        </listitem>
         <listitem>
           <para>[matthew] - Upgrade to readline-5.1.004.</para>
         </listitem>
diff --git a/chapter01/whatsnew.xml b/chapter01/whatsnew.xml
index a96b24483..b0025f631 100644
--- a/chapter01/whatsnew.xml
+++ b/chapter01/whatsnew.xml
@@ -64,9 +64,9 @@
     <listitem>
       <para>Findutils &findutils-version;</para>
     </listitem>
-    <!--<listitem>
+    <listitem>
       <para>Flex &flex-version;</para>
-    </listitem>-->
+    </listitem>
     <listitem>
       <para>Gawk &gawk-version;</para>
     </listitem>
@@ -254,6 +254,9 @@
   <itemizedlist>
     <title>Removed:</title>
 
+    <listitem>
+      <para>flex-2.5.31-debian_fixes-3.patch</para>
+    </listitem>
     <listitem>
       <para>gcc-3.4.3-linkonce-1.patch</para>
     </listitem>
diff --git a/chapter03/packages.xml b/chapter03/packages.xml
index 424fa8a80..0e5813a01 100644
--- a/chapter03/packages.xml
+++ b/chapter03/packages.xml
@@ -129,7 +129,7 @@
     </varlistentry>
 
     <varlistentry>
-      <term>Flex (&flex-version;) - 672 KB:</term>
+      <term>Flex (&flex-version;) - 679 KB:</term>
       <listitem>
         <para><ulink url="&sourceforge;flex/"/></para>
       </listitem>
diff --git a/chapter03/patches.xml b/chapter03/patches.xml
index c4f01469e..9a6132cbc 100644
--- a/chapter03/patches.xml
+++ b/chapter03/patches.xml
@@ -74,13 +74,6 @@
       </listitem>
     </varlistentry>
 
-    <varlistentry>
-      <term>Flex Brokenness Patch - 156 KB:</term>
-      <listitem>
-        <para><ulink url="&patches-root;&flex-fixes-patch;"/></para>
-      </listitem>
-    </varlistentry>
-
     <varlistentry>
       <term>Gawk Segfault Patch - 1 KB:</term>
       <listitem>
diff --git a/chapter06/flex.xml b/chapter06/flex.xml
index 3d375d311..1f33675ea 100644
--- a/chapter06/flex.xml
+++ b/chapter06/flex.xml
@@ -26,7 +26,7 @@
 
       <seglistitem>
         <seg>0.1 SBU</seg>
-        <seg>22.5 MB</seg>
+        <seg>21.3 MB</seg>
       </seglistitem>
     </segmentedlist>
 
@@ -44,18 +44,6 @@
   <sect2 role="installation">
     <title>Installation of Flex</title>
 
-    <para>Flex contains several known bugs. Fix these with the following
-    patch:</para>
-
-<screen><userinput>patch -Np1 -i ../&flex-fixes-patch;</userinput></screen>
-
-    <para>The GNU autotools detects that the Flex source code has been
-    modified by the previous patch and tries to update the man page
-    accordingly. This does not work correctly on many systems, and the
-    default page is fine, so make sure it does not get regenerated:</para>
-
-<screen><userinput>touch doc/flex.1</userinput></screen>
-
     <para>Prepare Flex for compilation:</para>
 
 <screen><userinput>./configure --prefix=/usr</userinput></screen>
diff --git a/general.ent b/general.ent
index 2bbbaa55c..430c82cce 100644
--- a/general.ent
+++ b/general.ent
@@ -42,7 +42,7 @@
 <!ENTITY expect-lib-version "5.43">
 <!ENTITY file-version "4.17">
 <!ENTITY findutils-version "4.2.27">
-<!ENTITY flex-version "2.5.31">
+<!ENTITY flex-version "2.5.33">
 <!ENTITY gawk-version "3.1.5">
 <!ENTITY gcc-version "4.0.3">
 <!ENTITY gettext-version "0.14.5">
diff --git a/patches.ent b/patches.ent
index aa11478af..c960066bd 100644
--- a/patches.ent
+++ b/patches.ent
@@ -14,8 +14,6 @@
 
 <!ENTITY expect-spawn-patch "expect-&expect-version;-spawn-1.patch">
 
-<!ENTITY flex-fixes-patch "flex-&flex-version;-debian_fixes-3.patch">
-
 <!ENTITY gawk-segfault-patch "gawk-&gawk-version;-segfault_fix-1.patch">
 
 <!ENTITY gcc-specs-patch "gcc-&gcc-version;-specs-1.patch">