Description:
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// $line equals line below from file:
$route['infox/(.*)'] = "articles/$1";

Basically I have to manually put an \ in front of the / char after infox. preg_quote() wont escape it and the documentation doesnt say i need to escape / chars. preg_match() is forcing me to put one there. 

Reproduce code:
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From manual page: function.preg-quote
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$urlClass = '\$route\['infox'/\(\.\*\)'\]';

preg_match("/$urlClass/", $line);

Expected result:
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no errors

Actual result:
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Message: preg_match() [function.preg-match]: Unknown modifier '\'

if i use $urlClass = '\$route\['infox'\/\(\.\*\)'\]';

it works (notice the \ infront of the 3rd char after infox)