If you are upgrading from version 1.2 to version 1.3 of symfony you may run into some odd filter issues after following their online guide @ http://www.symfony-project.org/tutorial/1_4/en/upgrade.

The main problem I had with this upgrade was the syntax construct for filters.yml has completely changed. This was a struggle b/c there was no mention of the change in the upgrade guide and I obviously didn’t want to completely replace my project files (nor did the guide say I had to). After some digging around I found the following link; http://www.symfony-project.org/reference/1_4/en/12-Filters, which demonstrates how the filters.yml file should be constructed. After following the new syntax construct example, I was able to successfully load my site.

Seems odd that the symfony devs don’t acknowledge this change on their ‘how to upgrade’ page.