API Contact get fails when search string contains apostrophe

The contact get API function fails to return any records when a search string contains an apostrophe, e.g. last_name => "O'Reilly".

To reproduce this on the demo environment, go to the API Explorer ( http://drupal.demo.civicrm.org/civicrm/api/explorer ), select Contact, get, and and a parameter to the query string to search for an existing contact whose name contains an apostrophe, e.g. household_name=Sheila Smith's home. You will get no results. Now replace the apostrophe with a % and you will get the result you should have got before.

From examining the MySQL log file it seems that each apostrophe is being prefixed by three backslashes, e.g. ' becomes \\\'. Each apostrophe should be prefixed by a single backslash, not three backslashes. It seems likely that the API is unnecessarily escaping the search string twice, so ' becomes \' becomes \\\'.