Build directory has expired or unused

Hello all,

After upgrade to teamcity 6.5 we have problem that build agent delets working directory . Tried to use option :

system.teamcity.agent.build.checkoutDir.expireHours=never

But it has no effect .

In logs I see : INFO - l.directories.DirectoryMapImpl - Delete <buid number>. Build directory has expired or unused

In file ../work/directory.map

Checked bt2=<Name>::trunk-nightly -> <Build number> |?| May 17, 2011 1:21:50 PM EEST |:| never

But it all has no effect .