Error #2048 Security sandbox violation – cannot load data

I get the below error when i am trying to make a java call from flex.

[RPC Fault faultString="Send failed"
faultCode="Client.Error.MessageSend"
faultDetail="Channel.Security.Error error
Error #2048: Security sandbox violation:
'http://sample.com/sample.swf' cannot
load data from
http://sample:8080/messagebroker/amf.
url:
'http://sample:8080/messagebroker/amf'"]

When i tried running the same in my local tomcat server, this was working fine. But when hosted as a site, i am getting this error. I tried placing the crossdomain.xml file in the root directory too. But the error would never go. crossdomain file is like below.

<cross-domain-policy>

<site-control permitted-cross-domain-policies="all" />

<allow-access-from domain="*"  to-ports="*"/> 

<cross-domain-policy/>

The logs says this

Connection to
'http://sample:8080/messagebroker/amf'
halted – not permitted from
http://sample.com/sample.swf.

has anyone faced a similar problem in hosting a flex site?