Homeowners are once again rushing to refinance their mortgages as rates continue to hold at or near record lows, but demand for purchase loans is weaker than it was at this time last year.Worries that the European debt crisis will trigger another global recession makes bonds and other conservative investments -- including the guaranteed mortgage-backed securities that fund most home loans -- look like safe havens to investors. Increased demand for those investments has pushed yields down.Rates on 30-year fixed-rate mortgages averaged 3.78 percent with an average 0.8 point for the week ending May 24, down from 3.79 percent last week and 4.6 percent a year ago, Freddie Mac said in releasing the results of its latest Primary Mortgage Market Survey. That's a new low in Freddie Mac records dati...