Thank you for taking the time to write to us, but this is not
a bug.

Removed the forward slash delimiters and it works. Manual should note that delimiters are not required (in fact, it will not work if the delimiters are provided).

This bug has been fixed in CVS.

In case this was a documentation problem, the fix will show up at the
end of next Sunday (CET) on pecl.php.net.

In case this was a pecl.php.net website problem, the change will show
up on the website in short time.
 
Thank you for the report, and for helping us make PECL better.

You can use the same expression format as ext/pcre. It uses now the extension API.

I'm reopening this bug because, now, FILTER_VALIDATE_REGEXP always appear to return FALSE (even if removing the forward slash delimiters).

EXAMPLE CODE:

<?php

// $_GET['name'] = 'John Doe'
$name = 'John Doe';

$expression = '/^[[:alpha:]\ \-\']+$/';
$options = array('regexp' => $expression);

var_dump(filter_input(INPUT_GET, 'name', FILTER_VALIDATE_REGEXP, $options));

var_dump(preg_match($expression, $_GET['name']));

var_dump(filter_var($name, FILTER_VALIDATE_REGEXP, $options));

var_dump(preg_match($expression, $name));

?>

EXPECTED RESULT:

string(8) "John Doe"
int(1)
string(8) "John Doe"
int(1)

ACTUAL RESULT:

bool(false)
int(1)
bool(false)
int(1)

I'm closing this bug because my last comment was bogus. I should've been passing the options arguments like this:

array('options' => array('regexp' => $expression))

So, the comment wasn't even related to the earlier problems described here. The API simply changed, and I didn't notice it.