Student-loan borrower woes are spilling over into the bond market as an increasing share of federal student-loan borrowers are entering into repayment plans that allow them to make smaller payments than they actually owe on the loans, according to new data out Friday, the Wall Street Journal reported yesterday. Some of these plans allow borrowers to make no payments. The trend has become an area of concern for a pool of federal loans that were originated by banks and other private lenders until 2010. Borrowers are still paying down these loans, and nearly $159 billion of them back bonds, according to the data from research firm MeasureOne.