Report Builder and Report Server cross domain communication

I have client machine in one domain, say A domain , on which I have installed .net 2.0 without any problem. I have report server running in other domain (B domain) where I have deployed few models which will be used from domain A to create ad hoc reports by launching Report Builder. I can access other reports in domain B from A

But when I click on Report Builder ..it tries to connect to server in domain B but fails to connect and shows following log in a text pop up

I know, problem is because of cross domain communication but question is then how to fix it ? what changes I need to do for that in firewall, domain etc etc settings?

Here is the error, I have highlighted lines which might give some clue:

PLATFORM VERSION INFO
Windows : 5.2.3790.65536 (Win32NT)
Common Language Runtime : 2.0.50727.42
System.Deployment.dll : 2.0.50727.42 (RTM.050727-4200)
mscorwks.dll : 2.0.50727.42 (RTM.050727-4200)
dfdll.dll : 2.0.50727.42 (RTM.050727-4200)
dfshim.dll : 2.0.50727.42 (RTM.050727-4200)

SOURCES
Deployment url : http://192.168.1.197/ReportServer/ReportBuilder/ReportBuilder.application

ERROR SUMMARY
Below is a summary of the errors, details of these errors are listed later in the log.
* Activation of http://192.168.1.197/ReportServer/ReportBuilder/ReportBuilder.application resulted in exception. Following failure messages were detected:
+ Downloading http://192.168.1.197/ReportServer/ReportBuilder/ReportBuilder.application did not succeed.
+ The remote server returned an error: (500) Internal Server Error.

COMPONENT STORE TRANSACTION FAILURE SUMMARY
No transaction error was detected.

WARNINGS
There were no warnings during this operation.

OPERATION PROGRESS STATUS
* [12/19/2006 6:49:58 AM] : Activation of http://192.168.1.197/ReportServer/ReportBuilder/ReportBuilder.application has started.

ERROR DETAILS
Following errors were detected during this operation.
* [12/19/2006 6:50:14 AM] System.Deployment.Application.DeploymentDownloadException (Unknown subtype)
- Downloading http://192.168.1.197/ReportServer/ReportBuilder/ReportBuilder.application did not succeed.
- Source: System.Deployment
- Stack trace:
at System.Deployment.Application.SystemNetDownloader.DownloadSingleFile(DownloadQueueItem next)
at System.Deployment.Application.SystemNetDownloader.DownloadAllFiles()
at System.Deployment.Application.FileDownloader.Download(SubscriptionState subState)
at System.Deployment.Application.DownloadManager.DownloadManifestAsRawFile(Uri& sourceUri, String targetPath, IDownloadNotification notification, DownloadOptions options, ServerInformation& serverInformation)
at System.Deployment.Application.DownloadManager.DownloadDeploymentManifestDirectBypass(SubscriptionStore subStore, Uri& sourceUri, TempFile& tempFile, SubscriptionState& subState, IDownloadNotification notification, DownloadOptions options, ServerInformation& serverInformation)
at System.Deployment.Application.DownloadManager.DownloadDeploymentManifestBypass(SubscriptionStore subStore, Uri& sourceUri, TempFile& tempFile, SubscriptionState& subState, IDownloadNotification notification, DownloadOptions options)
at System.Deployment.Application.ApplicationActivator.PerformDeploymentActivation(Uri activationUri, Boolean isShortcut)
at System.Deployment.Application.ApplicationActivator.ActivateDeploymentWorker(Object state)
Inner Exception
System.Net.WebException
- The remote server returned an error: (500) Internal Server Error.
- Source: System
- Stack trace:
at System.Net.HttpWebRequest.GetResponse()
at System.Deployment.Application.SystemNetDownloader.DownloadSingleFile(DownloadQueueItem next)

COMPONENT STORE TRANSACTION DETAILS
No transaction information is available.

After spending one night, I have fixed this problem myself

In IIS you should allow anonymous access to folder ReportServer/ReportBuilder folder and thats it....

One night's effort to fix a bug in 30 seconds...what a waste :-(

Prashant