diff --git a/dspace/jsp/dspace-admin/list-formats.jsp b/dspace/jsp/dspace-admin/list-formats.jsp
index 537cfa7b4f..f9c7811bbf 100644
--- a/dspace/jsp/dspace-admin/list-formats.jsp
+++ b/dspace/jsp/dspace-admin/list-formats.jsp
@@ -52,6 +52,9 @@
 <%@ taglib uri="http://www.dspace.org/dspace-tags.tld" prefix="dspace" %>
 
 <%@ page import="org.dspace.content.BitstreamFormat" %>
+<%@ page import="org.dspace.core.Context"%>
+<%@ page import="org.dspace.app.webui.util.UIUtil"%>
+
 
 <%
     BitstreamFormat[] formats =
@@ -87,6 +90,8 @@
         </tr>
 
 <%
+    Context context = UIUtil.obtainContext(request);
+
     String row = "even";
     for (int i = 0; i < formats.length; i++)
     {
@@ -109,7 +114,14 @@
                     <input type="text" name="mimetype" value="<%= formats[i].getMIMEType() %>" size=14>
                 </td>
                 <td class="<%= row %>RowOddCol">
-                    <input type="text" name="short_description" value="<%= formats[i].getShortDescription() %>" size=10>
+                    <%
+                      if (BitstreamFormat.findUnknown(context).getID() == formats[i].getID()) {
+                    %>
+                      <i><%= formats[i].getShortDescription() %></i>
+                    <% } else { %>
+                      <input type="text" name="short_description" value="<%= formats[i].getShortDescription() %>" size=10>
+                    <% } %>
+
                 </td>
                 <td class="<%= row %>RowEvenCol">
                     <input type="text" name="description" value="<%= formats[i].getDescription() %>" size=20>
@@ -132,7 +144,13 @@
                     <input type="submit" name="submit_update" value="Update">
                 </td>
                 <td class="<%= row %>RowOddCol">
+                    <%
+                      if (BitstreamFormat.findUnknown(context).getID() != formats[i].getID()) {
+                    %>
                     <input type="submit" name="submit_delete" value="Delete...">
+                    <% 
+                      } 
+                    %>
                 </td>
             </tr>
         </form>
diff --git a/dspace/src/org/dspace/content/BitstreamFormat.java b/dspace/src/org/dspace/content/BitstreamFormat.java
index 55972e0790..8519cc72e9 100644
--- a/dspace/src/org/dspace/content/BitstreamFormat.java
+++ b/dspace/src/org/dspace/content/BitstreamFormat.java
@@ -409,8 +409,12 @@ public class BitstreamFormat
      *            the new short description
      */
     public void setShortDescription(String s)
+       throws SQLException
     {
-        bfRow.setColumn("short_description", s);
+        // You can not reset the unknown's registry's name
+        BitstreamFormat unknown = findUnknown(bfContext);
+        if (unknown.getID() != getID())
+            bfRow.setColumn("short_description", s);
     }
 
     /**
@@ -562,12 +566,15 @@ public class BitstreamFormat
                     "Only administrators can delete bitstream formats");
         }
 
-        // Remove from cache
-        bfContext.removeCached(this, getID());
-
         // Find "unknown" type
         BitstreamFormat unknown = findUnknown(bfContext);
 
+        if (unknown.getID() == getID())
+	     throw new IllegalArgumentException("The Unknown bitstream format may not be deleted."); 
+
+        // Remove from cache
+        bfContext.removeCached(this, getID());
+
         // Set bitstreams with this format to "unknown"
         int numberChanged = DatabaseManager.updateQuery(bfContext,
                 "UPDATE bitstream SET bitstream_format_id=" + unknown.getID()