aor, my preference for such things, is a 1 part urethane based sealer such as auto windshield sealer...there are specific products such as SikaFlex 221, 252 and 3m 5200 but they can be hard to find...the auto windshield, also known as Evil Black Stuff, can be found at any auto body supplier and most auto parts store...
madjack
p.s for a cheaper fix, look for WhiteLightning 3006, an acrylic based ADHESIVE, with silicones in it...less than 4 bucks a tube(vs 10-15) at many box stores...I have been using this lately and have been impressed with it so far and unlike the urethanes, it can be cleaned up with water and comes in several colors........MJ
...I have come to believe that, conflict resolution, through violence, is never acceptable.....................mj