Development Java Linux Red Hat Software

jpackages error: Missing Dependency: /usr/bin/rebuild-security-providers

Jpackages on Red Hat has a nifty bug that causes dependency errors.

Luckily, somebody has created a fix as a rpm package 🙂

rpm -ivh jpackage-utils-compat-el5-0.0.1-1.noarch.rpm

And then jpackages works.

Linux Software

ImportError: No module named trac

When working with a new Trac installation you can bump into the error message “ImportError: No module named trac”. This is usually caused by Trac installation not unzipping all the needed files.

The following one liner should fix the issue:

cd /usr/lib/python2.4/site-packages;unzip Trac-0.12.2-py2.4.egg
Linux Red Hat

package subversion-1.6.12-0.1.el5.rf.x86_64 (which is newer than subversion-1.4.2-4.el5_3.1.i386) is already installed

Package conflict that can appear some times, a simple fix then is to downgrade first, then upgrade:


yum --downgrade update subversion
yum update subversion

Tips for implementing a custom JAAS login module for Jetty

1) jetty-web.xml

You can gather all specific settings for Jetty in the file WEB-INF/jetty-web.xml, remember to also specify paths for the role principals if you use your own classes for that.

Example jetty-web.xml file:

<!-- Jetty specific config file -->

<!-- Tell jetty where to find login config -->
<Call name="setProperty">

<!-- Bug fix for Jetty to properly handle login config in a per-project setup -->
<Set name="serverClasses">
	<Array type="java.lang.String">

<!-- Create login realm -->
<Get name="securityHandler">
	<Set name="userRealm">
			<Set name="name">*NAME OF YOUR REALM*</Set>
			<Set name="LoginModuleName">*NAME OF YOUR LOGIN CLASS*</Set>
			<Set name="roleClassNames">
				<Array type="java.lang.String">

2) Adding roles to a user in commit

When you want to give a user roles(like admin, moderator etc), you can add those to the user when he or she is authenticated and commit is called upon:

	public boolean commit() throws LoginException {
		MyUserPrincipal user = new MyUserPrincipal("username");

		//Add logged in user as first principal

		//Add roles for the logged in user
		subject.getPrincipals().add( new MyGroupPrincipal("admin") );
		subject.getPrincipals().add( new MyGroupPrincipal("moderator") );
Twitter Web

List of people twittering about Libya

Blog post last updated 16:04 GMT, 23.february 2010

This is a manually updated list of people twittering about the clashes that have now spread to Libya

Note: please comment if you miss anybody/anything here.

Twitter accounts updated within the last hour:
feb17voices, tweets about ti
alihabibi1, tweets about it
F_albinali, tweets about it
BBC World news, tweets about it
AJEnglish, tweets about it
Jnoubiyeh, tweets about it

Twitter accounts updated within the last three hours:

Twitter accounts updated later: