After installing the Java 6 RPM on Fedora Core (jdk-1.6.0-fcs), Nautilus prints the following error when you try to open an OpenOffice document:

The filename "Report.sxw" indicates that this file is of type "OpenOffice Writer". The contents of the file indicate that the file is of type "Java Archive". If you open this file, the file might present a security risk to your system.

This is because the file /usr/share/mime/packages/x-java-archive.xml that is created by the Java RPM is broken. To fix it, add a "<" in front of the second "match" tag:

--- x-java-archive.xml.orig     2006-12-24 14:47:05.000000000 +0100
+++ x-java-archive.xml  2006-12-25 11:57:03.000000000 +0100
@@ -32,7 +32,7 @@
     <glob pattern="*.jar"/>
     <magic priority="85">
       <match type="string" value="PK\003\004" offset="0">
-       match type="host16" value="0xcafe" offset="40" />
+       <match type="host16" value="0xcafe" offset="40" />
       </match>
     </magic>
   </mime-type>

Then run the following command:

update-mime-database /usr/share/mime

Log out and log in again to restart Nautilus.

Update 12 Jan 2007: This has been filed as ticket 6510610 in Sun's Bug Database.

Update 7 Jul 2007: The bug has been fixed in Java 6 Update 2.