This post relates to the significant number of warnings I was getting about ereg_replace being deprecated.
The offending call is in database.inc.php ln71. The PHP website http://php.net/manual/en/function.ereg-replace.php says that this function was deprecated from PHP 5.3.0 - the version I'm using. Some further reading suggests that this should be replaced with a call to preg_replace() but that needs a small tweak to the regex pattern - preg patterns must be delimited so I just added a / at start and end:
// PATCH: ereg_replace is deprecated
//$sql = ereg_replace("([,\(=])[\r\n\t ]*''",'\\1NULL',$sql);
$sql = preg_replace("/([,\(=])[\r\n\t ]*''/",'\\1NULL',$sql);
That got rid of the warnings although no guarantees the code is doing exactly what it was meant to!
I suspect its my setup that's 'caused' this problem. I'm running WAMPServer 2.0i. That's not the recommended AMP stack but then I was familiar with it and didn't want to setup another system. However, it would obviously be good if code wasn't using a deprecated function.