I just installed mongo 1.8.2 on a CentOS 64 bits server and try to create a replicate set using the following command:

> rs.initiate()
{
"info2" : "no configuration explicitly specified – making one",
"errmsg" : "couldn't initiate : can't find self in the replset config",
"ok" : 0
}
>

The mongod is started with the following and there are no other replication set on the subnet:

mongod --fork --rest --replSet osm

I've created replicate set without any issues with 1.6.5 on other 32 and 64 bits servers.