Suricata

The following rules do not error in Suricata 3.2.1 or Suricata version 4.0dev (rev 3ff5dc3):

alert tcp any any -> any any (msg:"DUAL REV TEST"; content:"|31 36 30 39 31 33 32 30|"; sid:3031; rev:1; rev:1;)

alert tcp any any -> any any (msg:"DUAL REV TEST"; content:"|31 36 30 39 31 33 32 30|"; sid:3032; rev:1; rev:2;)

It appears to pick the latter one when presented with two:

09/12/2016-14:51:13.407898 [**] [1:3032:2] DUAL REV TEST [**] [Classification: (null)] [Priority: 3] {TCP} 172.16.71.200:42439 -> 172.16.71.162:88