diff --git a/reference/apc/ini.xml b/reference/apc/ini.xml
index c1803a7a32..4aaa0b23e2 100644
--- a/reference/apc/ini.xml
+++ b/reference/apc/ini.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.22 $ -->
+<!-- $Revision: 1.23 $ -->
 <section xml:id="apc.configuration" xmlns="http://docbook.org/ns/docbook">
  &reftitle.runtime;
  &extension.runtime;
@@ -320,7 +320,11 @@
       needed by another entry.  Leaving this at zero
       means that your cache could potentially fill up
       with stale entries while newer entries won't be
-      cached.
+      cached.  In the event of a cache running out of
+      available memory, the cache will be completely
+      expunged if ttl is equal to 0.  Otherwise, if the
+      ttl is greater than 0, APC will attempt to remove
+      expired entries.
      </para>
     </listitem>
    </varlistentry>
@@ -331,10 +335,16 @@
     </term>
     <listitem>
      <para>
-      The number of seconds a user cache entry is allowed to idle in a slot in
-      case this cache entry slot is needed by another entry. Leaving this at
-      zero means that your cache could potentially fill up with stale entries
-      while newer entries won't be cached.
+      The number of seconds a cache entry is allowed to
+      idle in a slot in case this cache entry slot is
+      needed by another entry.  Leaving this at zero
+      means that your cache could potentially fill up
+      with stale entries while newer entries won't be
+      cached.  In the event of a cache running out of
+      available memory, the cache will be completely
+      expunged if ttl is equal to 0.  Otherwise, if the
+      ttl is greater than 0, APC will attempt to remove
+      expired entries.
      </para>
     </listitem>
    </varlistentry>