4.6.5 search regression on custom fields where option values have brackets

This works fine in 4.6.4 but is reproducable on the latest demo

To reproduce - create a customfield with a value that has parentheses in the option value value field
Image taken on http://d46.demo.civicrm.org/civicrm/admin/custom/group/field?reset=1&action=browse&gid=11 on an advanced multiselect field.

I edited a contact to have all the options for this field & he could be found by searching on the other chapters - but not the parenthesis one

I realise it might seem a little odd to have a parenthesis in an option value - but the UI has always permitted this & has generally encouraged the values matching the label.

This is a recent regression (fine in 4.6.4 but not in 4.6.5) so I think fixing it for this week's release should be a priority