[Zope-CMF] returning case insensitive matches for portal_membership.searchMembers()

[Norbert Marrale]

Hello

Is there a less expensive way to return case insensitive results when 
querying portal_membership? (Zope 2.7.5-final / CMF 1.5.5)

member = string.lower(REQUEST['userid'])
emails = context.portal_membership.searchMembers('email','')

   for n in range(0,len(emails),1):
     if (member==string.lower(emails[n].values()[1])):
       REQUEST.set('userid',str(emails[n].values()[0]))
       context.portal_registration.mailPassword(REQUEST['userid'], REQUEST)

Thanks in advance,

Norbert Marrale