Semisecure Login Reimagined (SLR) is a really good utility for users they haven't possibility to use SSL. But SLR doesn't work with PHP 5.4. Some errors occurs while encryption step. I wondering but then I found a workaround and created a inofficial update. But I think its better the developer change the plugin. So I hope he read this post.
More informations about this topic and workaround you'll find here: http://www.privalnetworx.de/index.php/2012/semisecure-login-reimagined-call-time-pass-by-reference-has-been-removed/