problem with streaming replication

Hi
i tried to do streaming replication following the tutorial at
http://wiki.postgresql.org/wiki/Binary_Replication_Tutorial

but i stoped at a problem and cant find nothing in google
when i start the slave server it starts ... and tels
LOG: database system was shut down in recovery at 2012-05-07 14:17:32 BRT
LOG: entering standby mode
LOG: restored log file "00000001000000000000006F" from archive
LOG: consistent recovery state reached at 0/6FDD9510
LOG: record with zero length at 0/6FDD9510
LOG: database system is ready to accept read only connections
FATAL: could not start WAL streaming: unexpected response from server; first
received character was "W"

the last line repeats ad eternum ...
i tried to search for it in google but no luck
my postgres in master is 9.1.2
and in slave is 9.1.3

I understood that this kind of version mismatch was supported, am i wrong ?

thanks a lot
Caio Boiteux