Mayor Bloomberg wants Gov. Paterson to veto a bill that would let low-income people getting housing assistance from the H.I.V./AIDS Services Administration pay no more than 30% of their incom e on rent. Bloomberg says the bill would cost the city an extra $15 million it doesn't have. (Besides, he's already committed $41.5 million in taxpayer money to make Governors Island pretty!) "As sympathetic as we are to the people who this would help, this nevertheless is yet another unfunded mandate from Albany, and one that will have significant immediate and long-term costs," Bloomberg spokeswoman Jessica Scaperotti told the Times. State Senator Tom Duane said the bill could actually save the city money by reducing the number of evictions and placements in emergency housing.