While developing a Dancer application recently, I started using SQL sentences with a REGEXP filter in them. Which resulted in a strange error...
As I found out, SQLite's implementation of the REGEXP function is quite incomplete.
Solution for now:
Make sure you've got a properly updated DBD::SQLite driver for your DBI. Newer versions have a hotfix regexp function that is based on Perl regexes.
The other solution:
Roll your own regexp implmentation, like this.