iproute, setting manually rtt

 I try to set some time values in iproute, and confused by results. Here 
 is example:

 bytecruncher ~ # ip route del 1.1.1.1;ip route add 1.1.1.1 via 
 217.151.224.113 rtt 10ms                                                 
                                                     bytecruncher ~ # ip 
 route
 1.1.1.1 via 217.151.224.113 dev eth0  rtt 3363235ms

 bytecruncher ~ # ip route del 1.1.1.1;ip route add 1.1.1.1 via 
 217.151.224.113 rtt 10ms rto_min 10ms
 bytecruncher ~ # ip route
 1.1.1.1 via 217.151.224.113 dev eth0  rtt 3363235ms rto_min lock 
 14100654ms

 Details about system:
 bytecruncher ~ # uname -a
 Linux bytecruncher 2.6.37.1-insat #4 SMP Tue Feb 22 15:16:53 EET 2011 
 x86_64 Intel(R) Xeon(R) CPU X5680 @ 3.33GHz GenuineIntel GNU/Linux
 bytecruncher ~ # ip -V
 ip utility, iproute2-ss110107

 I guess there is something really wrong. Not sure if in iproute or 
 kernel side.