Per the Jets official twitter feed:
Right Tackle Austin Howard signed his RFA tender.—
New York Jets (@nyjets) April 15, 2013
Howard would have had until the end of the week to try and get an offer sheet from another team, but this now ensures he will be under contract for 2013. The Jets will still have the option to try and sign him to a longer term detail should they choose to do so.
Despite a slow start, Howard ended up with PFF’s 8th best run blocking grade for all NFL tackles in 2012 (4th best for right tackles) and improved his pass protections numbers as the season went on (34 total pressures surrendered in the first eight games, just 16 in the last eight).