PHP 5.5 rc2 was recently uploaded to Debian unstable by Ondřej Surý. Along side the new PHP version and its features the PHP team has dealt with the JSON extension being non-free because of the “The Software shall be used for Good, not Evil” license (see debian #692613).
php5 (5.5.0~rc1+dfsg-1) experimental; urgency=low [...] * Add dfsg-repack.sh script to remove non-free JSON module (Closes: #692613) * Remove php5-json from Provides, since that's no longer true -- Ondřej Surý <firstname.lastname@example.org> Fri, 17 May 2013 14:41:41 +0200
A package with a DFSG replacement for the JSON extension is waiting in the NEW queue and should be available soon. The new JSON extension was done by Remi Collet (PHP developer and Fedora’s PHP maintainer). Review and patches are welcomed, code is available at https://github.com/remicollet/pecl-json-c . I hope the PHP project will adopt the solution, after claiming they won’t fix it themselves (see php.net #63520).