Find contacts box not searching well on first name

From this page

http://sandbox.civicrm.org/civicrm/contact/view/participant&reset=1&action=add&context=standalone

typing 'mi' in the find contact box doesn't return "smith, michael" (but typing ", mi" does)

It may be the answer is something along the lines of

multipleSeparator:"~",

(this worked for the 'commas problem' I had in an autocomplete: http://civicrm.org/node/528)