Bamboo is not Checking out the SVN Externals

Hi,

I am using Subversion 1.6.6 (r40053) and Bamboo [Atlassian Confluence 4.3.3].

I have project which has svn external definition in the same repository.

1. /svn/PolicyEngine_ER1304$ svn propget svn:externals .
   etc/postauth_users http://isppe.in.telstra.com.au/svn/freeRADIUS2/trunk/BigPond/auth/postauth_users
   bin/dictionary.cisco http://isppe.in.telstra.com.au/svn/freeRADIUS2/trunk/share/dictionary.cisco

When I build from bamboo, it is not checking out the svn external files.

The following error is observed in the bamboo log files,
-------------------
2012-12-10 12:09:35,425 ERROR [BAM::nsdaldevz01::Agent:pool-2-thread-1] [BuildLoggerUpdateEventHandler] Update of external at '/pub/bamboo/nsdaldevz01/bamboo-agent-home/xml-data/bui
ld-dir/BPPOLICYENGINE-01/etc/postauth_users' has been skipped: svn: Error while dispatching event: null
2012-12-10 12:09:35,462 ERROR [BAM::nsdaldevz01::Agent:pool-2-thread-1] [BuildLoggerUpdateEventHandler] Update of external at '/pub/bamboo/nsdaldevz01/bamboo-agent-home/xml-data/bui
ld-dir/BPPOLICYENGINE-01/bin/dictionary.cisco' has been skipped: svn: Error while dispatching event: null
-------------------

Could you please offer comment?

Thanks,
Raj.