Xdebug loaded correctly in Ubuntu but var_dump/error handling not being over-ridden

I have recently upgraded to Ubuntu 10.04 and as usual installed xdebug from the package manager. I've never had a problem after that with getting the formatted error messages and var_dumps to show up but this time they don't.

I ran phpinfo() and it is definitely loading i开发者_JAVA技巧t, and I even tried running some of the custom xdebug functions and all is working fine, but when I do a var_dump it comes up as though xdebug isn't installed. Any ideas why this is happening?

xdebug overloads the default var_dump function with its own, which means some settings may be carried over from the default PHP configuration. Specifically, make sure html_errors = On.

It's also possible that the xdebug package added some non-default configuration options. Specifically in this case, make sure xdebug.overload_var_dump = 1.